ini·​tial·​ism | \ i-ˈni-shə-ˌli-zəm How to pronounce initialism (audio) \

Definition of initialism

: an abbreviation formed from initial letters

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What is the difference between the words acronym and initialism?

Acronym is a fairly recent word, dating from the 1940s, although acronyms existed long before we gave them that name. The term was preceded in English by the word initialism, meaning an abbreviation formed from the initial letters of a phrase, and which has been in use since the late 19th century.

Some people feel strongly that acronym should only be used for terms like NATO, which is pronounced as a single word, and that initialism should be used if the individual letters are all pronounced distinctly, as with FBI. Our research shows that acronym is commonly used to refer to both types of abbreviations.

Examples of initialism in a Sentence

Recent Examples on the Web Gallucci argued that the Trump goal, which went by the initialism CVID and demanded full capitulation upfront, was never realistic. Jamie Mcintyre, Washington Examiner, "Rethinking North Korea: How bad would it be to let Kim Jong Un keep his nuclear weapons?," 19 Nov. 2020 With the posting of the original image to Instagram, captioned with the simple and chic initialism DTMH, Solange was one of many who called out a publication for false representation. Kate Branch, Vogue, "10 Times Beauty Got Political in 2017," 21 Dec. 2017 At the time of Lord Fisher’s letter, at the close of World War I, Britain must have seemed awash in initialisms. WSJ, "OMG! It Started in 1917 With a Letter to Churchill," 8 Sep. 2017 Playing with these initialisms didn’t end with Lord Fisher. WSJ, "OMG! It Started in 1917 With a Letter to Churchill," 8 Sep. 2017 The question is just how abbreviated should this initialism be? Bill Daley,, "Why LGBT initialism keeps growing," 2 June 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'initialism.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of initialism

1844, in the meaning defined above

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The first known use of initialism was in 1844

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Cite this Entry

“Initialism.” Dictionary, Merriam-Webster, Accessed 23 Apr. 2021.

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