A three-letter acronym (TLA), or three-letter abbreviation, is as the phrase suggests an abbreviation consisting of three letters. The abbreviation for TLA, TLA, has a special status among abbreviations and to some is humourous since abbreviations that are three-letters long are very common and TLA is, in fact, a TLA.
TLA is autological.
Most TLAs are initialisms (the initial letter of each word of a phrase), but most are not acronyms in the strict sense since they are pronounced by saying each letter, as in APA /ˌeɪpiːˈeɪ/ AY-pee-AY. Some are true acronyms (pronounced as a word) such as CAT (as in CAT scan) which is pronounced as the animal.
Examples
- Academic testing: ACT, SAT
- Air Navigation Services (ANS): AIS, ATC, ATM, ATS, CNS, FIS, MET, and SAR
- IATA airport codes: LAX and LHR
- Business: CEO, CFO, and other C-level officers
- Canine registries: AKC and CKC
- Chemistry, biology, and pharmaceuticals: GMO, LSD, and MSG
- Clinical medicine: CAD, CHF, PSA, and SOB
- Communications shorthand: LOL and OMG
- Computer phrases: CPU, DOS, RAM, ROM, and GNU
- Corporations: BMW, IBM, AMD, KFC and NEC
- Countries: SRI, USA, CAR, UAE, DRC, etc.
- Currency: USD, GBP, and CHF
- Famous people: SRK, FDR, JFK, MJK, MLK, OBL, RBG, RDJ, RFK, and RMS
- File extensions: JPG, PDF, and XLS
- Military and weaponry: BFR and RPG
- Musical groups: R.E.M., XTC, TLC, E.L.O., MC5, GBH, O.A.R., MDC, D.R.I., JFA
- Personal advertisements: SBM for Single Black Male, STR for Short Term Relationship
- Political Parties: BJP, CCP, GOP, and AAP
- Religion: LDS, SBC, and SDA
- Ship prefixes: HMS, USS, and RMS
- Sports organizations: NFL, MLB, (North America); AFL, and NRL (Australia); NPB (Japan); ACB, LFP (Spain); IPL (India), EPL (England), WBO
- State postal abbreviations: NSW, QLD, VIC, and TAS (Australia)
- Television networks: ABC (Australia, U.S.), BBC (UK), CBC (Canada, Japan), and NHK (Japan)
- Three-letter agencies: CIA, FBI, CBI, FSB, and NSA
- Traffic offenses: DUI, DWI, GTA, OVI
- Wars and political conflicts: HYW and WWI
History and origins
The exact phrase three-letter acronym appeared in the sociology literature in 1975.[1] Three-letter acronyms were used as mnemonics in biological sciences, from 1977[2] and their practical advantage was promoted by Weber in 1982.[3] They are used in many other fields, but the term TLA is particularly associated with computing.[4] In 1980, the manual for the Sinclair ZX81 home computer used and explained TLA.[5] The specific generation of three-letter acronyms in computing was mentioned in a JPL report of 1982.[6] In 1988, in a paper titled "On the Cruelty of Really Teaching Computing Science", eminent computer scientist Edsger W. Dijkstra wrote (disparagingly), "No endeavour is respectable these days without a TLA"[7] By 1992 it was in a Microsoft handbook.[8]
Combinatorics
The number of possible three-letter abbreviations using the 26 letters of the alphabet from A to Z (AAA, AAB, ... to ZZY, ZZZ) is 26 × 26 × 26 = 17,576. An additional 26 × 26 × 10 = 6,760 can be produced for each single position allowed to be a digit 0-9, such as 2FA, P2P, or WW2, giving a total of 37,856 such three-character strings.
Out of the 17,576 possible TLAs that can be created using 3 uppercase letters, at least 94% of them had been used at least once in a dataset of 18 million scientific article abstracts. Three-letter acronyms are the most common type of acronym in scientific research papers, with acronyms of length 3 being twice as common as those of length 2 or 4.[9]
In standard English, WWW is the TLA whose pronunciation requires the most syllables—typically nine. The usefulness of TLAs typically comes from its being quicker to say than the phrase it represents; however saying 'WWW' in English requires three times as many syllables as the phrase it is meant to abbreviate (World Wide Web). "WWW" is sometimes abbreviated to "dubdubdub" in speech.[10]
See also
- Acronym
- Alphabet agencies
- ISO 4217 (currency code)
- List of abbreviations in photography
- List of computing and IT abbreviations
- List of three-letter broadcast call signs in the United States
- List of three-letter combinations having Wikipedia articles
- Lists of acronyms
- Lists of airports by IATA and ICAO code
- Q code
- Recursive acronym
- Country code § Lists of country codes by country