Acronym

An acronym is an abbreviation formed using the initial letters of a multi-word name or phrase. Acronyms are often spelled with the initial letter of each word in all caps with no punctuation.

In English, the word is used in two ways. In the narrow sense, an acronym is a sequence of letters (representing the initial letters of words in a phrase) when pronounced together as a single word, like NASA, NATO, or laser. In the broad sense, the term includes this kind of sequence when pronounced letter by letter (such as GDP or USA). Sources that differentiate the two often call the former acronyms and the latter initialisms or alphabetisms. However, acronym is popularly used to refer to either concept, and both senses of the term are attributed as far back as the 1940s. Dictionary and style-guide editors dispute whether the term acronym can be legitimately applied to abbreviations which are not pronounced as words, and there is no general agreement on standard acronym spacing, casing, and punctuation.

The phrase that the acronym stands for is called its expansion. The meaning of an acronym includes both its expansion and the meaning of its expansion.

Etymology

The word acronym is formed from the Greek roots akro-, meaning 'height, summit, or tip', and -nym, 'name'. This neoclassical compound appears to have originated in German, with attestations for the German form Akronym appearing as early as 1921. Citations in English date to a 1940 translation of a novel by the German writer Lion Feuchtwanger.

Dispute over the scope of acronym

English lexicography and style guides differ on whether acronym should apply only to abbreviations pronounced as ordinary words or also to letter-by-letter initialisms. Some authorities accept or record the broader sense; others restrict acronym to word-pronounced forms and prefer initialism (or simply abbreviation) for the rest. Among sources that acknowledge the broader sense, attitudes range from neutral recording to prescriptive criticism.

Dictionaries

Some mainstream English dictionaries from across the English-speaking world affirm a sense of acronym that does not require its pronunciation as a word. American English dictionaries such as Merriam-Webster, Dictionary.com's Random House Webster's Unabridged Dictionary and the American Heritage Dictionary as well as the British Oxford English Dictionary and the Australian Macquarie Dictionary all include a sense in their entries for acronym equating it with initialism, although The American Heritage Dictionary criticizes it with the label "usage problem". However, many English language dictionaries, such as the Collins COBUILD Advanced Dictionary, Cambridge Advanced Learner's Dictionary, Macmillan Dictionary, Longman Dictionary of Contemporary English, New Oxford American Dictionary, Webster's New World Dictionary, and Lexico from Oxford University Press do not acknowledge such a sense.

Style and usage guides

English language usage and style guides which have entries for acronym generally criticize the usage that refers to forms that are not pronounceable words. Fowler's Dictionary of Modern English Usage says that acronym "denotes abbreviations formed from initial letters of other words and pronounced as a single word, such as NATO (as distinct from B-B-C)" but adds later "In everyday use, acronym is often applied to abbreviations that are technically initialisms, since they are pronounced as separate letters." The Chicago Manual of Style acknowledges the complexity ("Furthermore, an acronym and initialism are occasionally combined (JPEG), and the line between initialism and acronym is not always clear") but still defines the terms as mutually exclusive. Other guides outright deny any legitimacy to the usage: Bryson's Dictionary of Troublesome Words says "Abbreviations that are not pronounced as words (IBM, ABC, NFL) are not acronyms; they are just abbreviations." Garner's Modern American Usage says "An acronym is made from the first letters or parts of a compound term. It's read or spoken as a single word, not letter by letter." The New York Times Manual of Style and Usage says "Unless pronounced as a word, an abbreviation is not an acronym."

In contrast, some style guides do support it, whether explicitly or implicitly. The 1994 edition of Merriam-Webster's Dictionary of English Usage defends the usage on the basis of a claim that dictionaries do not make a distinction. The BuzzFeed style guide describes CBS and PBS as "acronyms ending in S".

Historical development and antedating

Most of the dictionary entries and style guide recommendations regarding the term acronym in the twentieth century did not explicitly acknowledge or support the expansive sense. The Merriam–Webster's Dictionary of English Usage from 1994 is one of the earliest publications to advocate for the expansive sense, and all the major dictionary editions that include a sense of acronym equating it with initialism were first published in the twenty-first century. The trend among dictionary editors appears to be towards including a sense defining acronym as initialism: the Merriam-Webster's Collegiate Dictionary added such a sense in its 11th edition in 2003, and both the Oxford English Dictionary and The American Heritage Dictionary added such senses in their 2011 editions. The 1989 edition of the Oxford English Dictionary only included the exclusive sense for acronym and its earliest citation was from 1943. In early December 2010, Duke University researcher Stephen Goranson published a citation for acronym to the American Dialect Society e-mail discussion list which refers to PGN being pronounced "pee-gee-enn", antedating English language usage of the word to 1940. Linguist Ben Zimmer then mentioned this citation in his December 16, 2010 "On Language" column about acronyms in The New York Times Magazine. By 2011, the publication of the 3rd edition of the Oxford English Dictionary added the expansive sense to its entry for acronym and included the 1940 citation. As the Oxford English Dictionary structures the senses in order of chronological development, it now gives the "initialism" sense first.