variants or fanatical
Synonyms of fanaticnext
: marked by excessive enthusiasm and often intense uncritical devotion
they're fanatic about politics
a fanatic attention to details
fanatically adverb
fanaticalness noun

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The Fanatical Origin of Fan

There are a good number of etymological myths in the English language, stories about the origins of words (such as the widespread notion that posh originated as an acronym for “port out, starboard home”) which are, to put it kindly, inaccurate. But this does not mean that every vivid account of linguistic origin is fictitious. Many words, such as fan, do have colorful backstories.

Fan is generally–and very likely correctly–believed to be a shortened form of fanatic. The origin of fanatic (which can be traced back to the Latin word fanum, meaning “sanctuary, temple”) is less often commented on. In English, fan made an early appearance in the late 17th century only to disappear for two centuries, resurfacing in the late 19th century. In this later period of use, it often referred to the devoted observers of, or participants in, a sport. An 1885 article from The Kansas City Times, for example, contains the line “The base ball ‘fans’ of the ploice [sic] force and fire department engage in a ball game.”

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The Latin adjective fanaticus, a derivative of the noun fanum, meaning “temple,” originally meant “of or relating to a temple.” It was later used to refer to pious individuals who were thought to have been inspired by a god or goddess. In time, the sense “frantic, frenzied, mad” arose because it was thought that persons behaving in such a manner were possessed by a deity. This was the first meaning of the English word fanatic. This sense is now obsolete, but it led to the meaning “excessively enthusiastic, especially about religious matters.” The word later became less specific, meaning simply “excessively enthusiastic or unreasonable.” The noun fan, meaning “enthusiast,” is probably a shortening of fanatic.

Examples of fanatic in a Sentence

because of her fanatical views, her friends know better than to try to discuss the issues with her
Recent Examples on the Web
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The chance to work with Alexandre, who dissects cinema with the precision of a detective and the passion of a fanatic, is irresistible. Matthew Carey, Deadline, 13 May 2026 Her sister-in-law, Vanessa, is a lighthouse fanatic, and in 2020, in the waning days of summer, the women had driven from West Virginia to visit Frying Pan Tower. Lauren Collins, New Yorker, 27 Apr. 2026 Maybe only 22 percent of Americans would readily accept Homelander as their one true God, but his vision might also appeal to those Christians whose fanatic prejudices outweigh any specific loyalty to the Bible and its lessons in compassion. Ben Rosenstock, Vulture, 22 Apr. 2026 Iran’s fanatic Islamic political leadership team, including Supreme Leader Ayatollah Ali Khamenei, were all killed. Peter Lucas, Boston Herald, 21 Mar. 2026 See All Example Sentences for fanatic

Word History

Etymology

Latin fanaticus inspired by a deity, frenzied, from fanum temple — more at feast

First Known Use

1550, in the meaning defined above

Time Traveler
The first known use of fanatic was in 1550

Browse Nearby Words

Cite this Entry

“Fanatic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fanatic. Accessed 10 Jun. 2026.

Kids Definition

fanatic

adjective
fa·​nat·​ic fə-ˈnat-ik How to pronounce fanatic (audio)
variants or fanatical
: overly enthusiastic or devoted
fanatic noun
fanatically adverb
fanaticism
-ˈnat-ə-ˌsiz-əm
noun

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