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initialism

American  
[ih-nish-uh-liz-uhm] / ɪˈnɪʃ əˌlɪz əm /

noun

  1. a set of initials representing a name, organization, or the like, with each letter pronounced separately, as FBI for Federal Bureau of Investigation.

  2. acronym.

  3. the practice of using initials or forming words from initials.


Grammar

See abbreviation.

Usage

What does initialism mean? An initialism is a term formed by abbreviating a phrase by combining certain letters of words in the phrase (often the first initial of each) into a single term. Common examples of initialisms include FBI (an initialism of Federal Bureau of Investigation) and TMI (an initialism of too much information). What’s the difference between an acronym and an initialism?Initialism is sometimes used as a synonym for acronym, but most technically it refers to an abbreviation in which each initial is pronounced separately, as in FBI and TMI. Although acronym is sometimes used generally to refer to any term formed from this kind of abbreviation, it typically refers to ones that can be pronounced as a word, like NASA (an acronym for National Aeronautics and Space Administration) and FOMO (a slang acronym for fear of missing out). Still, most people don’t distinguish between acronyms and initialisms—they usually end up calling most abbreviations acronyms. Both terms are often associated with their use in certain fields that use a lot of technical terms, like science, tech, and the military. But they’re popular in all kinds of contexts since they’re an easy way to make long phrases much shorter. Example: MIA is an initialism that stands for “missing in action.”

Etymology

Origin of initialism

First recorded in 1895–1900; initial + -ism