tla

This article describes three-letter acronyms. For other uses of the term TLA, see TLA (disambiguation).

The TLA (Three-Letter Acronym or Abbreviation) is the most popular type of abbreviation in computing and telecom terminology and Internet slang, and is also common in political jargon. There is some disagreement about whether abbreviations like TLA actually constitute acronyms (see acronym and initialism), and this has led to the occasional use of the word abbreviation as opposed to acronym in expanding the term. However, the expansion "three letter acronym" is the older and more frequently cited one.

Background

"TLA" is, of course, a TLA itself; the term was almost certainly coined with a certain degree of self-referential humor in mind. Likewise, a four-letter abbreviation is sometimes known as a FLAB (Four Letter ABbreviation), an ETLA (Extended TLA), an LFLA (Longer Four Letter Abbreviation) or a TLA/E (TLA/Extended) - although all these are far less common than TLA. In the same vein, VLFLA is a Very Long Five Letter Abbreviation and DETLA is a Doubly-Extended Three Letter Abbreviation. TLAs became common in the United States during the New Deal of President Franklin Delano Roosevelt (who is frequently referred to as FDR). Terms from this period included NRA for National Recovery Administration, and TVA for the Tennessee Valley Authority. Detractors of President Roosevelt's policies called the new agencies "alphabet soup."

Description

Using only upper-case letters, there are 26³ = 17576 possible three-letter abbreviations, and probably most of them are already used in some context. If numbers, special characters, or case-sensitivity are allowed, even more TLAs can be created. Many TLAs have more than one meaning: TLA itself is also a TLA for the Theater of the Living Arts. There are many TLAs with more than 10 meanings (for example, SDI has at least 36 meanings in the English language). Furthermore, many abbreviations have more than one expansion with the same meaning. For example GCC was first 'GNU C Compiler', and later 'GNU Compiler Collection'. (See also backronym.) In the MS-DOS operating system for personal computers, because only three-letter file extensions (usually denoting the file type) were allowed, many longer abbreviations were shortened to three letters (for example JPEG to JPG, HTML to HTM), and many of these are still used. DOS itself is a TLA for 'Disk Operating System' as well. Many abbreviations, some of them TLAs, come from the shortened names of Usenet groups. For example pra for pl.rec.anime.

Common categories of TLAs

household: PVC, PET
corporations: BBC, CNN, IBM, DEC
time zones: GMT, UTC, DST
sports: NFL, NBA, MLB, NHL
individuals: JFK, LBJ, GWB, FDR
politics: NGO, GOP, DNC, NDP, ANC, PAC
government: the American DOD, DOE, HUD, IRS, CIA, the British CPS, MOD, MI5, MI6, SIS, HRH
military: SAS, APC, POW
paramilitary: PLO, ETA, NPA, IRA, ASU of the IRA, various Northern Irish Loyalist groups, the Colombian left-wing ELN
medicine: AAA, EKG, EMT, MRI, PVC, TOE
drugs: ASA, THC, XTC, LSD, PCP
computers

file types: PNG, GIF, PDF
hardware: CPU, FPU, RAM, ROM, HDD, FDD
software: GCC, GTK
software licences: GPL, MPL
operating systems: GNU, BSD, DOS
programming languages: AWK, PHP, SQL
communications protocols: FTP, IRC, TCP

A significant number of TLAs come from various codes:

IATA airport codes: LAX, MSQ, SFO, NGO (see Lists of TLAs, below)
ISO 639 (language names): ara, eng, spa
ISO 3166-1 alpha-3 (country codes): USA, SCG, UAE
ISO 4217 (currency codes): RUR, USD
SIL codes for languages: ENG, FRN, SWD, BQT
IOC country codes: FRA, GBR, GER, JAP (see Lists of TLAs)
AAR railroad reporting marks: CNW, CSX, GBW

Tla

Background

Description

Common categories of TLAs

Lists of TLAs

See also