Acronym
An acronym is a word or name formed from the initial components of a longer name or phrase.
- Snippet from Wikipedia: Acronym
An acronym, a type of abbreviation, is a word or name consisting of parts of the full name's words. Some authorities add that an acronym must be pronounced as a single word rather than individual letters, so considering NASA an acronym but not USA; the latter they instead call an initialism or alphabetism, for a string of initial letters which are pronounced individually. Acronyms commonly are formed from initials alone, such as NATO, FBI, YMCA, GIF, EMT, and PIN, but sometimes use syllables instead, as in Benelux (short for Belgium, the Netherlands, and Luxembourg), NAPOCOR (National Power Corporation), and TRANSCO (National Transmission Corporation). They can also be a mixture, as in radar (Radio Detection And Ranging) and MIDAS (Missile Defense Alarm System).
Acronyms pronounced as words include SWAT and UNESCO, while ones pronounced as individual letters include CIA, TNT, NPC, BLM, and ATM. Some use elements of both, such as JPEG (JAY-peg), CSIS (SEE-sis), and IUPAC (I-U-pak). Some are not universally pronounced either way, but by speaker's preference or by context, such as SQL (either "see-kwel" or "ess-cue-el").
The broader sense of acronym, which includes terms pronounced as individual letters, is the word's original meaning and still in common use. Dictionary and style-guide editors dispute whether the term acronym can be legitimately applied to abbreviations which are not pronounced "as words," nor do they agree on acronyms' spacing, casing, and punctuation.