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Why Prep?

English Acronyms & Abbreviations

What is an

What is an

acro = topmost, highest, capitalnym = name

It is a name which uses the capital letters of a phrase
 (or first letters of a phrase).


a (to) + breviate (shorten) + ~ion (noun suffix)

It is a shortened word.

Technically acronyms are also a kind of abbreviation.

That's why I put them on the same page.



Special Note:

All content on this website is provided by Leon of Leonsplanet.com free of charge.  It is original content.  Yes, I may have done some research to find out what some of the acronyms are/mean, and to find some of the abbreviations (Google searches being my main source of information), but I (Leon) compiled all the information here on this page for easy reference to all of Leon's Planet users.  This content may be copied and used for educational purposes, but be sure to give me (Leon Priz) credit for compiling the information; and link to this page if at all possible.  ALSO!  If you have benefitted from my hard work, please consider donating by clicking on the Donate button in the left sidebar.


Table of Contents
...linked up for your convenience!

ACRONYMS A list of common acronyms in English
Business & Mail Abbreviations (including letters & postal abbreviations)
Calendar (and Holiday) Abbreviations      
Educational Abbreviations (including academic & scholarly abbreviations)
ESL  Abbreviations and Acronyms (by popular demand, I bring you ESL, EFL, TEFL, TESL abbreviations and acronyms)
Grammar Abbreviations  Grammar of the English Language (and dictionary abbreviations)
Government/Military Abbreviations (mostly US)
Health/Medical Abbreviations (including diet, food, and health abbreviations)
ICT Abbreviations (computer & internet abbreviations)
International Abbreviations Short list of common ones.
Mathematical Abbreviations (really cool!)
Organizational Abbreviations/Acronyms Other / Miscellaneous Category
People's Titles/Suffixes Abbreviations Dr., Mr., Mrs., etc. / Jr., Sr., etc.
Road Abbreviations Dr., Rd., St., Ave., etc.
Science Abbreviations Biology, Chemistry, Physics
Social and Texting Abbreviations (sports, entertainment, & fun abbreviations)
Time Abbreviations clock time, and calendar time


(Short Form)
Stands for...
CELTA Certificate in English Language Teaching to Adults [UK]
DADD Dad's Against Drunk Driving [US]
DARE Drug Abuse Resistance Education [US]
DELTA Diploma in English Language Teaching to Anyone [UK]
ERIC Educational Resource Information Center [US]
ESOL English as a Second or Other Language International
FIFA Fédération Internationale de Football Association International
IELTS International English Language Testing System [UK]
LADD Leon's Planet Against Destructive Decisions [US]
MADD Mothers Against Drunk Driving [US]
NATO North Atlantic Treaty Organization International
OPEC Organization of Petroleum Exporting Countries International
SADD Students Against Destructive Decisions [US]
TEFL Teaching English as a Foreign Language Worldwide
TESL Teaching English as a Second Language Worldwide
TESOL Teachers of English to Speakers of Other Languages Worldwide
TOEFL Test Of English a Foreign Language [US]
TOEIC Test of English for International Communication International 
UNICEF United Nations Int'l Children's Emergency Fund International

Did I miss some?  Please contact me, if so.




These are NOT acronyms, because they are NOT pronounced as words.
Each letter is pronounced individually.

One abbreviation I use a lot is "Ex."  It means "Example" (but this one is not used in spoken English).

Stands for...
401K Pension Plan Comes from the IRS Code, Section 401K.
& and Not used formally.
It is a kind of shorthand writing.
@ at Used for location and time-setting.
Apt. Apartment Appt. = Appointment
ASAP As Soon As Possible Say, "A-S-A-P" to mean, "As soon as possible."
Or just write "ASAP" (all caps) to mean "As soon as possible."
ATTN Attention
bcc back carbon copy Used in emails to keep someone informed, but that person cannot see all the other persons who were emailed the same notification.  Also known as...
CC carbon copy In the old days, when I was a kid working for my father, we actually used carbon paper to make carbon copies.  This was the most common way of copying before copy machines were invented.

Actual carbon paper is still used.  Here is a video to show one way that it can be used...

Nowadays, the 'cc' abbreviation is used in emails to keep another person (or others) informed who are NOT the intended recipient of the email.

For example, let's say I need to send an email to a coworker, but I want to keep my boss informed of the communication, I would 'cc' my boss.

Like this...
Date:  04/24/2022
To:  someone@someplace.com
RE:  Customer Support Issue
CC:  boss@homeoffice.com

Dear Someone,
     Is the customer support issue revolved that I brought to your attention yesterday?


CEO Chief Executive Officer ...
CFO Chief Financial Officer ...
CHRO Chief Human Resources Officer ...
c/o Care Of Used on postal envelopes where the recipient is different than the intended recipient.


COD Cash On Delivery This means that the recipient pays for the postage upon delivery.  (Not used much anymore).
DBA Doing Business As... ...
demo demonstration In business, a 'demo' (or 'demonstration') is a show; usually done to show how a product works.

(It is NOT a protest, in business contexts).

DIY Do It Yourself ...
e-mail (or 'email') electronic mail ...
fwd forward Means "to forward" an email to someone else who didn't get the original email, but needs to have that information (or would want to have that information).
FYI For Your Information ...
GM General Manager ...
HR Human Resources Also Known As (AKA) Personnel Department 
info information ...
lbs pounds Comes from the Latin word 'libras', which means pounds.
Ltd Limited A kind of business where the liability is limited to the organization and not any of the people working for the organization.
memo memorandum ...
N/A Not Applicable ...
no. number ...
PIA Payment In Advance ...
PO Box Post Office Box ...
     # # = pounds;  lbs (libras)

     [ libras is Latin for 'pounds'. ]

Ex.)  33# = 33 pounds (lbs)

Note:  We don't write 33lbs, because it looks like 331bs.  So, to avoid confusion and mistakes, we use 33#, especially in the shipping (logistics) industry.

# also means:  number Ex.)  #33 = number 33
# also means:  sharp (in music) Ex.)  C#, D#, F#, G#, A#
# has a different meaning in social media. See 'Social Media' section.
PO# Purchase Order Number ...
PR Public Relations ...
PS Post Script Written at the end of a letter as an afterthought.
R&D Research and Development ...
Re: Regarding ...
RSVP Répondez S'il Vous Plaît Respond If You Please
Ste. Suite A suite is like an apartment, but for business.
VAT Value Added Tax In some countries, you'll see this at hotels and expensive restaurants.  (The idea is to gouge tourists).
VIP  (or V.I.P.) Very Important Person A "VIP Room" would be a room reserved for Very Important People.
W2 Report of how much tax was withheld from one's pay, and given to the gov't in the form of income tax. Given 2 the employee.
W4 Document filled out by employees for the employer to know how much to withhold from the worker's pay for taxes. Filled out 4 the employer.
(I think now its referred to as a "1099" - [say Ten-ninety-nine].)
Document filled out by independent contractors, telling the IRS that the worker is an independent contractor and is responsible for his/her own taxes. ...
w/ with Informal writing.
w/o without Informal writing.



Road Abbreviations

Stands for...
Ave. Avenue  
Blvd. Boulevard  
Cir. Circle  
Ct. Court  
Dr. Drive We park on a driveway, and we drive on a parkway.  Learn more about crazy English.
Hwy. Highway  
Ln. Lane  
Pl. Place  
Pkwy. Parkway We park on a driveway, and we drive on a parkway.  Learn more about crazy English.
Rd. Road  
St. Street  
Terr. Terrace  




Peoples Titles and Suffixes

People's Titles
Stands for...
Dr. Doctor Title of one with a Ph.D. or equivalent.
Ms. Miss Title of unmarried woman.
Mr. Mister Title of a man.
Mrs. Mistress
Pronounced:  "Misses" 
Title of a married woman.
Mz. Miz Title of a woman (especially when it is not known whether the woman is married or not).
People's Suffixes
Stands for...
Esq. Esquire In the U.S.A., the suffix Esquire is reserved for a person licensed to practice law.
I First The first of a line of male progenitors which have the same name as their firstborn, male offspring.
II Second The second of a line of males which has the same name as his father.
III Third The third of a line of males which has the same name as the father and the grandfather.
Jr. Junior That suffix designates the male child with the same name as the father.
Sr. Senior That suffix designates the father with the same name as his son.



Educational Abbreviations

Stands for...
ACT American College Testing College entrance exam
ADD Attention-Deficit Disorder This is actually a medical diagnosis, but I include it here in this section because so many children these days are being diagnosed with the condition.
ADHD Attention-Deficit-Hyperactivity Disorder This is ADD + physical hyperactivity.
This can ONLY be diagnosed by a medical doctor, not a teacher.
AR Accelerated Reader A reading testing program online
BA Bachelor of Arts A 4-year college/university degree.
B-Ed Bachelor of Education say /Bee-Ed/
BS Bachelor of Science A 4-year degree from college/university.
CIE Cambridge International Examinations CIPP
CIPP Cambridge Int'l Primary Programme ...
CIS Council of International Schools ...
CPD C? Professional Development I'm not sure what the "C" actually stands for, but this is the British form of PD  (See PD).
CRT Critical Race Theory Basically says that all whites are racists and privileged, which of course is just not true, because no blanket statement like that is ever true.
CTT Cooperative Teacher Team Teachers of the same grade level or same subject.
DD Doctor of Dentistry ...
ECA Early Childhood Academy ...
ECE Early Childhood Education Grades Pre-K to 2
ELA English Language Arts ELA is what the U.S.A. calls its public-school English language education.
Homeschooling Parents please click here for ELA resources.
El.Ed. Elementary Education Grades 1 to 6
ELL English Language Learner ESL student  (See ESL)
ESL English a Second Language A program that helps students where English is not their first language.
ESP Extra Sensory Perception 6th sense
ESP English for Special Purposes A division (or subset) of EFL / TEFL
et al. and all ...refers to all those who helped
FOBISA Federation of British International Schools in Asia ...
IB International Baccalaureate  International High School Diploma
IGCSE International General Certificate of Secondary English International High School Diploma
IQ Intelligence Quotient 100/100 is normal
JD Juris Doctor of lawyers and attorneys
('solicitors' in the UK) 
LA Language Arts English Language Education for native speakers
LD Learning Disabled ...
LEA Local Education Authority ...
MA Master of Arts ...
MA,Ed Masters of Education ...
MAP Measures of Academic Progress A kind of standardized testing; used domestically and internationally.
MBA Master of Business Administration ...
MD Medical Doctor Doctor of Medicine
MR Mentally Retarded (This is a clinical term) There are 3 levels:  (1) mildly retarded, (2) moderately retarded, (3) severely retarded
MS Master of Science ...
NEA National Education Association ...
NSTA National Science Teachers' Association ...
ODD Oppositional-Defiant Disorder It's a real thing!  I've seen it!
PD Professional Development Teachers have to have on-going training, called "professional development".
PLC Professional Learning Community A group of teachers that work together for the benefit of their school.  Bigger than CTT (see CTT), but smaller than whole faculty of the school.
PM Post Meridian ...
PhD Philosophical Doctor Doctor of Philosophy
PSAT Practice Scholastic Aptitude Test Practice college entrance exam
PTA Parent-Teacher Association ...
PTO Parent-Teacher Organization ...
SAT Scholastic Aptitude Test College entrance exam
Sec.Ed. Secondary Education ...
SPED Special Education ...
SSR Silent-Sustained Reading ...






(clock, dates, etc.)
Stands for...
@ at Used for location and time-setting.

Ex.)  I'll meet you @ 8:00AM @ the meeting place.

AD  &  BC AD = Ano Domini (Year of Lord's [birth])
BC = Before Christ
AM  &  PM AM = Ante Meridian (Before Middle)
PM = Post Meridian (After Middle)
The middle is noon!
Appt. appointment  Apt. = Apartment
ASAP As Soon As Possible Say, "A-S-A-P" to mean, "As soon as possible."
Or just write "ASAP" (all caps) to mean "As soon as possible."
BC Before Christ Ex.)  The last time the red sun came around was circa 
bya billion years ago Geological Time
c. circa Latin word for "around".
cent. century The word "century" is Latin for 100.
DATE shorthand -> In the U.S.A. it is done this way:

Ex.)  04/24/2022

DOB or D.O.B. Date of Birth ...
ETA or E.T.A. Estimated Time of Arrival ...
hr. hours ...
min. minutes ...
mo. month ...
mya million years ago Geological Time
sec. seconds ...
TIME ZONES of the U.S.A. PST = Pacific Standard Time
MST = Mountain Standard Time
CST = Central Standard Time
EST = Eastern Standard Time
yr. years ...


ESL Abbreviations


Abbreviations & Acronyms
(I used to be in this field for many, many years)

Stands for...



CELTA Certificate in English Language Teaching to Adults [UK]
cent. century as in "15th cent." = 1400-1499
CIE Cambridge International Examinations CIPP
CIPP Cambridge Int'l Primary Programme ...
CR Consciousness Raising term "coined" by Rutherford
DDL Data-Driven Learning ...
DELTA Diploma in English Language Teaching to Anyone [UK]
dial. dialect ...
EFL English as a Foreign Language What's the difference between EFL and ESL?
ELC English Learning Center ...
ELT English Language Training ...
ESL English as a Second Language What's the difference between EFL and ESL?
ESP English for Special Purposes ...
IELTS International English Language Testing System ...
IGCSE International General Certificate of Secondary English [UK-recognized] International High School Diploma [UK]
IPA International Phonetic Alphabet Learn more here.
L1 First Language Mother Tongue
L2 Second Language Target Language
lang. language ...
ling. linguistic See also linguistic terms and abbreviations
MT Mother Tongue one's native language (first language)
NS Native Speaker ...
NNS Non-Native Speaker ...
phonet. phonetic, phonetically See my "Phon" page.
phonol. phonology, phonologically See my "Phon" page.
SLA Second Language Acquisition a branch of applied linguistics
TL target language the second language that one is trying to learn
TEFL Teaching English as a Foreign Language ...
TESL Teaching English as a Second Language ...
TESOL Teachers of English to Speakers of Other Languages an int'l TEFL/TESL organization
TOEFL Test Of English a Foreign Language by ETC
Learn how to write well for TOEFL.
TOEIC Test Of English for International Communication by ETC
tr. or transl. translation ...
[UK] United Kingdom British English
[US] United States American English
us., usually ...
vocab. vocabulary ...



Grammar Abbreviations

(Writing Abbreviations)

Abbreviations & Acronyms
(Also Dictionary Abbrev.)

Stands for...



abbrev. abbreviation ...
adj. adjective Learn more about parts of speech.
adv. adverb Learn more about parts of speech.
anat. anatomy, anatomical word part of the body
APA American Phonetic Alphabet Learn more here.
arch. archaic very old meaning of the word
art. article a, an, the
bot. botany, botanical word part of the plant kingdom
[C] Countable Seen in EFL / ESL dictionaries / lexicons.
See also [U].
cap capital letter caps = capital letters
cent. century as in "15th cent." = 1400-1499
cl. clause Meet the clauses.
colloq. colloquialism spoken English (not used in formal writing).
compar. comparative -er, more~
conj. conjunction [UK] connective

Learn more about parts of speech.

derog. derogatory bad word
dial. dialect Yes!  There are dialects of English.
e.g. er go   (That's Latin for:  "for example") ...
esp., especially ...
et al. and all [those who helped] ...
etc. et cetera  (That's Latin for:  "and so on") ...
etym. or etymol. etymology; etymologically origins of the word
Ex.) Example ...
f. feminine female word
fig. figurative figurative meaning
fut. future us., future tense
ger. gerund noun ~ing noun

Ex.)  Swimming is fun.

Gram. (or Gr.) grammar Leon's Grammar Page.
idiom idiomatic expression See idioms on Leon's Figure's of Speech Page.
i.e. id est (that is) ...
imp. imperative mood commands
infin. infinitive noun to + verb = noun

Ex.)  To swim is to have fun.

intj. interjection Learn more about parts of speech.
IPA International Phonetic Alphabet Learn more here.
lang. language See which languages Leon teaches.
Lat. Latin the word is of Latin origin
ling. linguistic See also linguistic terms and abbreviations
lit. literally literal meaning of the word
m. masculine of a word that is male/masculine
ME middle English English that was spoken from 12th to 15th centuries.
misc.  or  miscell. miscellaneous variety
n. noun Learn more about parts of speech.
Narr. narrative Learn how to write a narrative.
obj. object a noun that generally comes after the verb.
English is a SVO language, i.e., Subject-Verb-Object.
Obs. Obsolete old meaning of the word (not used anymore)
OE Old English English that was spoken before 12th century A.D.
opp. opposite of... ...
orig. original, originally from ...
pa. past us., past tense
pp     or     pa. pple. past participle gone, done, swum, drunk, etc.
pass. passive passive voice
phonet. phonetic, phonetically See my "Phon" page.
phonol. phonology, phonologically See my "Phon" page.
phr. phrase Leon's Page on Phrasal Verbs.
pl. plural more than one
pref. prefix Ex.)

Learn more here.

prep. preposition to, from, on, under, below, above, etc.

Learn more about parts of speech.

pres. present present tense (habitual tense)
pron. pronoun he, she, him, her, they, them, etc.

Learn more about parts of speech.

refl. reflexive himself, herself, etc.
reg. regular as in a regular verb.
(There are many irregular verbs).
sb somebody Seen as ((sb))
Seen ONLY in bilingual lexicons.
sing. singular one
sp. spelling ...
sth something Seen as ((sth))
Seen ONLY in bilingual lexicons.
subj. subject ...
subjunct. subjunctive mood I would...
I could...
I should...
subord. subordinate subord. cl.  =  subordinate clause
suff. suffix Ex.)

Learn more here.

superl. superlative -est, most~
syll. syllable(s) ...
[U] Uncountable Seen in EFL / ESL dictionaries / lexicons.

See also [C].

[UK] United Kingdom British English
[US] United States American English
us., usually ...
v. or vb. verb Learn more about parts of speech.
var. variation ...
veg. vegetable, vegetation the word is a type of vegetation
v.i. verb intransitive no object allowed for this verb.
vocab. vocabulary morphemes
v.t. verb transitive object required for this verb.
vulg. vulgar a word that has vulgar meaning
zool. zoology, zoological a zoological word



U.S. Gov't / Military

Gov't / Military
Stands for...
ATF & E Alcohol, Tobacco, Firearms & Explosives [US ] They mostly focus on firearms & explosives
CIA Central Intelligence Agency [US ] Intelligence gathering organization

The CIA Factbook is cool!

CBP Customs and Border Protection 'US]  What are these people doing?  Twiddling their thumbs?  And getting paid by the American people?  Jeeze!  I want that job!
CDC Center for Disease Control [US]  a highly corrupt organization.
Just follow the money.
Col. colonel  pronounced /kernel/
DEA Drug Enforcement Agency [US]
DHS Department of Homeland Security [US]  DHS
[UK]  Home Office
DMV Department of Motor Vehicles [US]
DMZ DeMilitarized Zone ...
DOD Department of Defense [US] Military
DOT Department of Transportation [US]
ELE Extinction Level Event Get the scoop on what's coming to a planet near you!
EMP Electo-Magnetic Pulse
is a weapon to ruin all electronics.
See also HEMP.

EMPs can also come from Coronal Mass Ejections (CMEs) from the sun.

Click on logo learn how to get $50-off promo-code from Leonsplanet.com

EPA Environmental Protection Agency [US]
FAA Federal Aviation Administration [US] Air Control
FBI Federal Bureau of Investigation [US] National Police
FCC Federal Communications Commission [US]
FDA Food and Drug Administration [US]
government ...
GVW Gross Vehicle Weight  ...
HEMP High-altitude Electro-Magnetic Pulse A nuclear device detonated high in the altitude above the target.  
INS Immigration & Naturalization Service ...doesn't exist anymore! (as of 2003)

see USCIS, ICE, and CBP

ICE Immigration and Customs Enforcement ...
IRS Internal Revenue Service [US]
JAG Corps Judge Advocate General's Corps Military  Lawyers Group
KIA Killed In Action  ...
Lt. lieutenant   ...
MI Military Intelligence This is an oxymoron.   Don't get me wrong.  I support the soldiers with all my heart.  It's the intelligence department that needs work.
MIA  /  POW MIA = Missing In Action

POW = Prisoner of War

MP [UK] MP = Member of Parliament
[US] MP = Military Police
MRE Meal Ready to Eat  
NAFTA North American Free Trade Agreement  
NATO North Atlantic Treaty Organization  
NSA National Security Agency [US]
NV Night Vision  
OSHA Occupational Safety & Health Administration
POW Prisoner Of War  
Sgt. sergeant   
SOF Special Operations Force(s)  
SOS Save Our Ship  Used in Morse Code.
TTG Time To Go  
UN United Nations  
USAF United States Air Force  
USCG United States Coast Guard  
USCIS United States Citizenship & Immigration Services  
USMC United States Marine Corps  
USN United States Navy  
WMD Weapon of Mass Destruction  



International Abbreviations

Stands for...
APEC Asia-Pacific Economic Cooperation  
ASEAN Association of South East Asian Nations  
CCP Chinese Communist Party China is technically NOT communist anymore, but the party still exists and is in power.
DPRK Democratic People's Republic of Korean
AKA:  North Korea
The DPRK country is probably more democratic than the U.S., and DPRK is a known dictatorship.
DMZ DeMilitarized Zone Between North and South Korea
I've been there!  I've even visited PanMunGeom.
ELE Extinction Level Event Coming soon!
FIFA Fédération Internationale de Football Association In English, that's:  International Federation of Soccer (Football) Association
MIA Missing in Action See also POW.
NAFTA North American Free Trade Agreement (probably doesn't exist anymore, but if it does, it has been amended).
NATO North Atlantic Treaty Organization Basically consists of U.S.A. and Europe.
POW Prisoner Of War


ROK Republic of Korea
AKA:  South Korea
I lived there!  Read my blog.
UN United Nations  ...
WMD Weapon of Mass Destruction  Is a High-altitude Electo-Magnetic Pulse (HEMP) weapon considered a WMD?  It wipes out all electronics in a 50-mile radius (I made that number up).  That throws us back to the stone age.  Mad Max-scenarios ensue.


How to be prepared.
Click on image below to find out.



Health Abbreviations

Medical / Health
(including diet, food, & health)
Stands for...
ADD Attention Deficit Disorder This ONLY can be diagnosed by a medical doctor.
ADHD Attention Deficit / Hyperactivity Disorder This can ONLY be diagnosed by a medical doctor.
AIDS (acronym) Acquired ImmunoDeficiency Syndrome ...a disease caused by HIV
AMA American Medical Association [US]
BP Blood Pressure ...
CDC Center for Disease Control [US]  ...a highly corrupt organization.
Just follow the money.
DOA Dead On Arrival ...
EMT Emergency Medical Technician ...
GMO Genetically Modified Organism ...
HIV Human Immunodeficiency Virus The virus that causes AIDS
ICU Intensive Care Unit For people in danger of dying.
IV Intravenous For putting fluids into the blood stream.
Intra = into
venus = vein
MSG Mono-Sodium Glutamate meat tenderizer and flavor enhancer
(really bad for your body!)
Do your own research!
ODD Oppositional Defiant Disorder ...
PMS Pre-Menstrual Syndrome ...
RDA Recommended Daily Allowance ...
R&R Rest and Relaxation ...
SIDS (acronym) Sudden Infant Death Syndrome ...
stat Photostat "stat" means immediately
VAIDS Vaccine-induced Acquired Immuno-Deficiency Syndrome The vaccine that causes AIDS.



Organizational Abbreviations


(NOT government or military) NGO
Meaning More
AA Alcoholics Anonymous [US]
AAA (say, "Triple A") American Automobile Association [US]
BBB Better Business Bureau [US]
CFR Council on Foreign Relations International
DADD (acronym) Dad's Against Drunk Driving [US]
IOC International Olympic Committee  International
LADD Leon's Planet Against Destructive Decisions On my site.
MADD (acronym) Mothers Against Drunk Driving [US]
NGO Non-Government Organization Anywhere
OPEC (acronym) Organization of Petroleum Exporting Countries International
SADD (acronym) Students Against Drunk Driving [US]
UN United Nations International
WHO (say: W-H-O; not "hoo") World Health Organization International
WWE World Wrestling Entertainment [US]
WWF World Wildlife Fund International



Social Abbreviations
& Texting Abbreviations

(Day-to-day stuff, sports, entertainment, and fun)
Stands for...
Stands for...
ADMIN administration 121 one to one
AKA Also Known As 2
tonite / tonight
A.S.A.P. As Soon As Possible 4
ATM Automatic Teller Machine B be
ATV All Terrain Vehicle 2GTBT to good to be true
B.A. Bad Attitude C U l8tr see you later
B-ball Basketball IOU I owe you.
B-day Birthday R are
BFF Best friends, forever Y why
BM Bowel Movement YRU here Why are you here?
BS "Bull Sh**" BRB Be Right Back
BYOB Bring Your Own Beer BTW By the way
CHL Canadian Hockey League cuz 'cause
DOB Date of Birth DKDC Don't know; don't care.
DUI Driving Under the Influence DLBBB
Don't let the bed bugs bite.
DWI Driving While Intoxicated DL,  D/L Download
ET Extra Terrestrial  (Alien to Earth) DM Direct Message
ETA Estimated Time of Arrival EZ easy
FAQ (acronym) Frequently Asked Question FB facebook
FAX (acronym) Facsimile FOMO Fear of missing out
FYI For Your Information FUBAR "fouled" up beyond all recognition
GIGO Garbage In;  Garbage Out G2G Got to go
Gov't Government GG
Good Game
Good Game; Well Played
HOV High-Occupancy Vehicle GL2U Good luck to you
ICC International Cricket Council IDK I don't know.
ID Identification IKR I know, right?
j/k just kidding ILY I love you.
K.I.S.S. Keep It Simple, Stupid.
Keep It Simple, Silly!
K? Okay?
IDK I Don't Know. IDK I don't know.
IU I love you. ISO In search of...
LOL Lots of Love LOL Laughing Out Loud
MLB Major League Baseball LMK Let me know.
N/A Not Applicable LMAO
Laughing my ass off
Laughing my "freaking" ass off
MSG Mono-sodium glutamate msg message
NBA National Basketball Association Mod Moderator, modification
NBL National Basketball League MYOB Mind your own business.
NCAA National Collegiate Athletic Association NASL

(or ASL)

Name, Age, Sex, Location

(HINT:  Don't give your real name to strangers online!!!)

NFL National Football League NOYB None of your business
NHL National Hockey League NVM Never mind.
PDQ Pretty Darn Quick OFC OF course
PIN Personal Identification Number OMG Oh, my God
pop popular PLZ Please
PS Post Script PM Private Message
Q&A Questions and Answers QT cutie
R.I.P. Rest In Peace
say: /ar-ai-pee/
do NOT say /rip/.
Rolling on the floor laughing
RPG Role Playing Game RLY really
R&R Rest and Relaxation RUOK Are You O.K.?
RSVP Repondez s'il vous plait
(French: "Respond if you please")
S.O.L. Sh** Out of Luck
SOS Save Our Souls SMH Shaking my head
SUV Sports Utility Vehicle STFU Shut the f*** up
(This is bad language)
Tech Technician  TBH To be honest, ...
Techno Technology Music THX Thanks
TGIF Thank God It's Friday TLDR Too long; Didn't read.
TLC Tender Loving Care TMI Too Much Information
TP Toilet Paper TTFN Ta Ta for now
TV Television TTYL Talk to ya later
UFO Unidentified Flying Object U R ... You are...
VAT Value Added Tax VM Voice Mail
VCR Video Cassette Recorder VWD Very well done
VIP Very Important Person VWP Very well played
VTR Video Tape Recorder
Korean English
WTH What the h***?
(This is bad language)
WWF World Wrestling Federation WTF What the f***?
(This is bad language)
XOXO X = Kiss
O = Hug
YOLO You only live once.

R.I.P.  = Rest In Peace



Mathematical Abbreviations

Stands for..
0D zero dimensions a single point
1D one dimension a line
2D two dimensions a plane
3D three dimensions space
4D four dimensions time-space continuum (mostly TIME)
A Area cm2, m2, km2 
b base A (triangle) = 1/2 b * h
C capacity mL, L
cc's cubic centimeters
cL [US] centiLiters / [UK] centiLitres measurement of capacity
cm [US] centimeters / [UK] centimetres measurement of length
cos cosine function For Trigonometry
COS or coef coefficient In 2a, the "2" is the coefficient
d distance d = r ÷ t
E Electrical Force (voltage)
f frequency Frequency is measured in Hertz (Hz).
g grams measurement of mass
h height A (parallelogram) = b * h
kg kilograms measurement of mass
km [US] kilometers / [UK] kilometres measurement of length
l length A (rectangle) = l * w
L [US] liters / [UK] litres measure of capacity
log logarithm  For Trigonometry
m mass mass is measured in grams (g) or kilograms (kg)
mL [US] milliLiters / [UK] milliLitres measurement of capacity (C)
mm [US] millimeters / [UK] millimetres measurement of length
φ Phi (the golden mean) 1.618~ (the golden mean)
π Pi 3.14159~ (irrational number)
r radius (half the diameter of a circle) A (circle) = πr2 
Perimeter (circle) = 2πr
V (sphere) = 4/3 π r3
r rate r = m/s     r = d/t
s second measurement of time (t)
S Surface Area cm2, m2, km2 
sin sine function For Trigonometry
t time Time is measured in seconds (s)
tan tangent function For Trigonometry
V Volume cm3, m3, km3 
w width A (rectangle) = l * w



Science Abbreviations
Some common ones.  This is NOT a comprehensive list.

Astronomy Biology Chemistry Physics
CME = Coronal Mass Ejection (from the sun); these can cause EMPs, and thus cause radio and electric-grid disruptions.

EMP = Electro-Magnetic Pulse; these can be from the sun or artificial created by human-made devices.

HEMP = High-altitude Electro-Magnetic Pulse; these are cause by detonating a nuclear device in the atmosphere.

Click to get $50-off.

IRAS = Infra-Red Astronomical Satellite

ISS = International Space Station

NASA = National Aeronautical and Space Administration



ATP = AdenoTriPhophate

Bot. = Botany

DNA = DeoxyriboNucleic Acid

EPA = Environmental Protection Agency

mRNA = messenger RiboNucleic Acid

NOAA = National Oceanic and Atmospheric Administration

RNA = RiboNucleic Acid

WWF = World Wildlife Federation

Zoo = Zoological Garden

Zool. = Zoology


C = Carbon

C6H12O6 = Carbohydrate (Sugar)

CO = Carbon Monoxide

CO2 = Carbon diOxide

H = Hydrogen

First photo of hydrogen atom


H2O = 2 Hydrogen atoms bonded to 1 Oxygen atom (Water)

H2O2 = Hydrogen per Oxide

MSG = MonoSodium Glutamate

N = Nitrogen (the element)

N2 = Nitrogen (the gas)

NaCl = Sodium Chloride (Table Salt)

NH3 = Hydrogen Nitride (Ammonia)

O = Oxygen (the element)

O2 = Oxygen (the gas)

O3 = Ozone

pH = per Hydrogen

pH Scale

1 3 5 7 9 11 14





AC/DC = Alternating Current / Direct Current

Amps = amperes (measurement of current)

E = Electromotive Force (measured in Newtons or Volts);  E = the force required to send 1 ampere (I) through 1 ohm (Ω).

I = Induction [AKA:  Current] (measured in amperes)

Ω = Ohms (measurement of resistance); 
1 ohm = the resistance offered when 1 volt pushes 1 amp of electrical current

Ohm's Law
I =V/R
or V=IR or R=V/I

P = Power (measured in Watts)

W = Watts (measurement of Power)

Watt's Law
P = IE
{Power (Watts) = Induction (Amps)  x Electrical Force (Voltage)}

EMP = Electro-Magnetic Pulse

EMS = Electro-Magnetic Spectrum

= (Lambda) measurement of wavelength; wavelength is measurement in meters.

T = Tesla (measurement of the strength of a magnetic field)

D = Density  (D = m ÷ V)
m = mass (mass is measured in grams)
V = Volume (Volume is measured in cm3V = l x w x h)

a =
acceleration  (m/s/s) or (m/s2)

A = Amplitude

c = celerity of light (186,000 miles per second)

E = Energy  (E = mc2)  Energy is measured in Joules (J)

F = Force (F = m x a); Force is measured in Newtons

J = Joules (measurement of energy and work)

= (Lambda) measurement of wavelength; wavelength is measurement in meters.

m = mass

M = Momentum (M = F x a)

N = Newtons (measurement of Force; 1 Newton is equal to 1 kg x 1m/s2.)

W = Work

P = Pressure (pressure is measured in Pascals)

Pa = Pascals (1N/m2)

PSI = Pounds per Square Inch



I.T. (Information Technology) &
(Information & Communications Technology) / Computer

I.T. / ICT
Stands for...

Byte a bit of technology.

b bit a single switch  (0 = off;  1= on)
B byte 1 byte = 8 bits
Kb, KB Kilobits;  KiloBytes 1000 bits = 125 bytes
1000 bytes = 8000 bits
Mb, MB Megabits;  MegaBytes 1,000,000 bits = 125,000 bytes
1,000,000 bytes = 8,000,000 bits
Gb, GB Gigabits;  GigaBytes 1,000,000,000 bits = 125,000,000 bytes
1,000,000,000 bytes = 8,000,000,000 bits
TB TeraBytes 1000000000000 bytes

Other techno stuff.

admin administrator owner or manager of the computer or network
ATM Automatic Teller Machine cash dispenser
CAD Computer-Aided Design  
cell phone cellular telephone a wireless telephone that uses a cell (battery)
CD Compact Disk  
cgi (as in "cgi bin") common gateway interface  
CGI computer-generated imagery  
.co commerce (business) [UK]
.com commerce (business) [US]
~com communication (s) Examples:  MobiCom, Telecom
DVD high-Density Video Disk Dense Video Disk
.edu education  
e-mail electronic mail  
fax facsimile  
ftp file transfer protocol  
.gov government  
HD High-Definition  
HDD Hard Disk Drive  
HDMI High-Definition Multimedia Interface Type of video cord.
HDTV High-Definition TeleVision  
Hi-fi high fidelity high level of quality
html hyper-text markup language  
http hyper-text transfer protocol  
https hyper-text transfer protocol secured  
ID Identification  
.int international  
IP Internet Protocol  
ISP Internet Service Provider  
IT Information Technology  
Mac Macintosh from Apple hardware
mobile mobile telephone a mobile wireless telephone
.org organization Non-government organization
PC Personal Computer from IBM (or similar hardware)
php "Personal Home Page" Tools It is a hypertext preprocessor using perl script, developed by Rasmus Lerdorf.
PIN Personal Identification Number This is mostly for Debit cards and ATMs.
RAM Random Access Memory Temporary Memory
ROM Read-Only Memory Permanent Memory
SEO Search Engine Optimization Link for more information on this topic
Technology Also, "Techno" is a genre of music, with sounds of technology in the background, usually in a percussionary function.
URL Uniform (or universal) resource locator, web address
USB Universal Serial Bus Thumb Drives & Flash Drives go into the USB
VGA Video Graphics Array Type of video cord.
Video-CD Video-Compact Disk These are obsolete (not produced anymore)
Wi-fi wireless fidelity wireless internet
www world-wide web ...



Calendar Abbreviations
(and Holiday Abbreviations)


Stands for..
A.D. Anno Domini (Year of the Lord) Anno Domini means the year Christ was born.
Used for counting years after Christ was born.
b-day birthday (at least I use this abbreviation all the time).
B.C. Before Christ We count backwards from the Birth of Christ in B.C.
B.C.E. Before Common Era Used instead of B.C.
I don't know why--maybe anti-Christians started using it.
C.E. Common Era Used instead of A.D. (probably by non-Christians).
Days of the Week -> Sunday = Sun's Day
Monday = Moon's Day
Tuesday = Tue's Day (god of war)
Wednesday = Wedne's Day (Wodin's day)
Thursday = Thur's Day (Thor's day)
Friday = Frigga's Day
Saturday = Saturn's Day
Note:  Saturday is from Latin and is not an English word.  Before it was called Saturday, it was called "Laundry Day"  (from Old Norse laugar dagr) which means washing day (not only for washing clothes, but also washing the body).

Source:  Scholarly Community Encyclopedia.


Hallowed Evening. The night of the last day of the Celtic calendar, when the gates of the Underworld were opened for one night.


All Hallowed Tide is a period of three days:
Oct. 31st = All Saint's Eve
Nov. 1st = All Saint's Day
Nov. 2nd = All Soul's Day

Juneteenth June nineteenth The day the slaves were emancipated (after the U.S. Civil War).
Months -> Jan.
NOTE:  The word "month" means "moon" (referring to one complete cycle of the moon).
St. Patrick's Day

Saint Patrick's Day. In order to become a 'saint', one must have completed a miracle and be beatified by the Pope.  (This only happens after the person has passed away).

Patrick is credited with several miracles, but the only one I can remember off the top of my head is driving all the snakes from Ireland.

St. Valentine's Day

Saint Valentine's Day. Valentine is credited with healing miracles.

Xpist-mass. Xpist is "Christ" in Greek.



Did I miss any?  Contact me.

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