A three-letter acronym, three-letter abbreviation, or TLA is an acronym, abbreviation, alphabetism or initialism consisting of three letters. These are usually the initial letters of words of the phrase abbreviated, and are written in capital letters (upper case): three-letter abbreviations such as "etc." or "Mrs." would not be described as a three-letter acronym.

Most three-letter abbreviations are initialisms (i.e., all the letters are pronounced as letters, as in LSD), and very few fit the narrow definition of acronym (which requires it to be pronounced as a single word, as in DOS, which is unusual in three-letter abbreviations). See acronym and initialism for discussion of the difference.

Nevertheless, three-letter acronym is a recognised phrase, often abbreviated to TLA. A series of lists of TLAs lists all TLAs which are included in Wikipedia. These lists also include abbreviations comprising two letters followed by a single digit, which are not strictly three-letter acronyms.

TLA has the recursive feature that TLA is its own TLA.

Examples

• Countries: USA and CIS.
• Politicians: JFK and LBJ.
• Computer Terms: RAM, CPU and DOS.
• Corporations: IBM and NEC.
• Three Letter Agencies: CIA, FBI, NSA, SAS.
• Television networks: ABC (U.S.) and BBC (U.K.).
• Personal advertisements: SBM for Single Black Male.
• Chemistry, biology, pharmaceuticals: MSG and LSD.
• Clinical medicine: CHF, CAD
• Communications shorthand: LOL and OMG.
• Military and weaponry: BFR and RPG
• IATA airport codes: SFO and LAX.
• Academic testing: SAT, ACT, and GRE.
• Tombstones: RIP

Wikipedia also has an exhaustive list of TLAs.

History and origins

Three-letter acronyms were used as mnemonics in biological sciences, and the exact term three-letter acronyms appeared in the literature in 1977^[1]. Their practical advantage was promoted by Weber in 1982^[2]. They are used in many other fields, but the term TLA is particularly associated with computing^[3].

The first known use of the self-referential term "TLA" was by Texas Instruments Inc. employees in the Industrial Systems Division circa 1982. Engineers used to mock the marketing department's tendency to define new products with three-word descriptions, such as "CVU" for a product line called "Control Vision Unit" and "ACM" for "Automation Configuration Module." Due to the seemingly excessive use of three-letter abbreviations or initialisms at the company, the employees started simply to report that they were working on product "TLA" as an ironic self-reference.

In 1988, eminent computer scientist Edsger W. Dijkstra wrote "Because no endeavour is respectable these days without a TLA ... "^[4] By 1992 it was in a Microsoft handbook.^[5]

Use of "TLA" spread through both industry and academia, and it has now become a generally understood initialism.^[6] For a complete discussion of the various forms of abbreviations, acronyms and other letter substitutions, see Acronym and initialism.

Other information

• 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. Another 26 × 26 × 10 = 6760 can be produced if the third element is allowed to be a digit 0-9, giving a total of 24,336.
• In English, WWW is the longest possible TLA to pronounce, requiring nine syllables. Although in written English it is an abbreviation, in spoken English it may use more syllables than that which it is abbreviating.^[7] See also Pronunciation of "www".
• YABA ("Yet Another Bloody Acroynm") is a related though less-used term. "YABA-compatible" is used to mean that term's acronym can be pronounced but is not an offensive word. (e.g., "When choosing a new name, be sure it is "YABA-compatible.")^[8]

References in popular culture

• As early as 1967, the musical Hair included the song "Initials", whose final verse consisted only of TLAs, viz: "LBJ IRT USA LSD. LSD LBJ FBI CIA. FBI CIA LSD LBJ."
• In 1986 Will Shatter of the band Flipper formed a band named "Any Three Initials" (ATI), as a parody of the preponderance of hardcore punk bands with three-initial names.
• In 1998 the British band Love and Rockets released their last album, Lift, featuring the song "R.I.P. 20 C." that, apart from the refrain, consists only of three-letter abbreviations. A contest was held rewarding the first to correctly give the meanings of all 69 of them.
• In 1999 German hip-hop group Die Fantastischen Vier (The Fantastic Four) released the song "MfG" ("Mit freundlichen Grüßen" - German for "best regards", literally "with friendly regards"), also mainly consisting of TLAs.^[9]
• In 1999, the author Douglas Adams remarked: "The World Wide Web is the only thing I know of whose shortened form takes three times longer to say than what it's short for."^[10]
• According to the Jargon File, a journalist once asked hacker Paul Boutin what he thought the biggest problem in computing in the 1990s would be. Paul's straight-faced response was, "There are only 17,000 three-letter acronyms."
• The Jargon File also mentions the term "ETLA" for "Extended Three Letter Acronym" to refer to four letter acronyms/abbreviations. Also, "Extended Three Letter Acronym" is sometimes abbreviated to "XTLA".

See also

• Category:Lists of TLAs
• RAS syndrome
• List of acronyms and initialisms
• List of all two-letter combinations
• List of computing and IT abbreviations
• List of three-letter broadcast callsigns in the United States
• List of airports by IATA code
• List of IOC country codes
• ISO 4217 (currency code)

Footnotes

1. ↑ S. R. Seavey & P. H. Raven (1977) Journal of Biogeography Vol 4 No 1 page 57
2. ↑ W. A. Weber (1982) Taxon Vol 31 no 1 "Mnemonic Three-Letter Acronyms for the Families of Vascular Plants"
3. ↑ K. D. Nilsen & A. P. Nilsen (1995) The English Journal, Vol 84 No 6 "Literary Metaphors and Other Linguistic Innovations in Computer Language"
4. ↑ On the cruelty of really teaching computer science
5. ↑ Dan Gookin (1992) The Microsoft Guide to Optimizing Windows page 211
6. ↑ See Wiktionary.
7. ↑ i.e. dou-ble-u dou-ble-u dou-ble-u = 9 syllables, whereas the most well-known expansion "World wide web", along with most of the entries on WWW (disambiguation), requires only 3 syllables.
8. ↑ K. D. Nilsen & A. P. Nilsen (1995) The English Journal Vol. 84, No. 6.,"Literary Metaphors and Other Linguistic Innovations in Computer Language"
9. ↑ Lyrics of "MfG"
10. ↑ Douglas Adams, The Independent on Sunday, 1999

External links

• Abbreviations.com ? A directory and search engine for acronyms, initialisms, and other abbreviations.
• Acronymfinder.com ? Resource to find multiple meanings of acronyms, sorted by type.
• TLA Wörterbuch - Casia TLA collection.
• GTF - the GPL'ed TLA FAQ.
• The Great Abbreviations Hunt - A TLA for every combination of letters.
• All Acronyms Dictionary ? Database of acronyms with thousands of TLAs
• AuctionSlanguage.com - A resource to find meanings of acronyms and abbreviations used on auction sites. Includes many TLA's like NWT and HTF.

da:TLA de:Dreibuchstabenabkürzung eo:Listo de 3-literaj kombina?oj fr:Sigles de trois lettres it:Three-letter acronym nl:DLA pl:Skróty trzyliterowe sl:Tri?rkovna kratica sv:TLA