acronym

noun

ac·​ro·​nym ˈa-krə-ˌnim How to pronounce acronym (audio)
: a word (such as NATO, radar, or laser) formed from the initial letter or letters of each of the successive parts or major parts of a compound term
also : an abbreviation (such as FBI) formed from initial letters : initialism
acronymic adjective
acronymically adverb

Frequently Asked Questions

What is the difference between an acronym and an initialism?

Both acronyms and initialisms are made up of the first letter or letters of the words in a phrase. The word acronym typically applies when the resulting thing can be read as a word; for example, radar comes from "radio detection and ranging" and scuba comes from "self-contained underwater breathing apparatus." The word initialism only applies when the resulting thing is read as an abbreviation; for example DIY, which comes from "do it yourself," is pronounced by saying the names of the letters. Note that the word acronym is also sometimes used to mean "initialism."

What is the difference between an acronym and an abbreviation?

An acronym is a kind of abbreviation. Abbreviations can be shortened forms of any kind. For example, appt is an abbreviation of appointment, and ASAP is an abbreviation of as soon as possible. ASAP, however, also qualifies as an acronym because it is made up of the initial letters of the phrase it comes from: as soon as possible.

Is OK an acronym?

OK is technically an acronym. It comes from the phrase "oll korrect," a humorous alteration of "all correct."

Examples of acronym in a Sentence

The North Atlantic Treaty Organization is known by the acronym “NATO.”
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
True to their name—an acronym for Rock Your Nuts Off—the band sometimes attracted the attention of police. Literary Hub, 10 Oct. 2025 Known by the acronym BESS, the systems can make grids more reliable and have been credited with reducing blackouts. Jessica Coacci, Fortune, 4 Oct. 2025 The bill is known by the rather unfortunate acronym NOPE. Jay Caspian Kang, New Yorker, 3 Oct. 2025 Thousands of Filipinos massed in the capital on the main Epifanio de los Santos Avenue, a historic highway known by its acronym EDSA, many either clad in white or wearing a white ribbon, and braving extreme heat and rain. Chad De Guzman, Time, 21 Sep. 2025 See All Example Sentences for acronym

Word History

Etymology

probably borrowed from German Akronym, Akronymon, from akr- acr- + -onym, -onymon -onym

First Known Use

1940, in the meaning defined above

Time Traveler
The first known use of acronym was in 1940

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Cite this Entry

“Acronym.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acronym. Accessed 12 Oct. 2025.

Kids Definition

acronym

noun
ac·​ro·​nym ˈak-rə-ˌnim How to pronounce acronym (audio)
: a word (as radar) formed from the beginning letter or letters of each or most of the parts of a compound term

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