: one who claims to know everything
also : one who disdains advice
know-it-all adjective

Examples of know-it-all in a Sentence

Recent Examples on the Web For aspiring know-it-alls, Princeton University Press sells a series of pocket-size encyclopedias covering subjects including brain phenomena and dinosaur lore. Ella Riley-Adams Angela Koh Jameson Montgomery Jameson Montgomery Tom Delavan, New York Times, 16 Nov. 2023 Williams portrayed the couple's seemingly perfect, know-it-all daughter, Laura. Ingrid Vasquez, Peoplemag, 16 Sep. 2023 Ginnie is bossy about other people’s behavior and Yvette is a know-it-all about diseases, having had so many. Jesse Green, New York Times, 13 Sep. 2023 Even so, who better than Tina Fey to play a self-important, slightly bullying know-it-all who conceals her questionable competence behind a thin layer of condescension? Todd Gilchrist, Variety, 9 Sep. 2023 One downside to sharing the up-close moments of Idalia’s aftermath on TikTok, Watson said, is the social media know-it-alls. Kalhan Rosenblatt, NBC News, 31 Aug. 2023 Side hustles for know-it-alls Notably, your knowledge doesn’t need to be encyclopedic or broad. Kathy Kristof, San Diego Union-Tribune, 7 Aug. 2023 Democrats think Republicans are knuckle-dragging idiots, and Republicans think Democrats are know-it-all twits. Cameron Smith |, al, 1 Aug. 2023 Patricia simply could not do the job, and in retrospect, putting a promising quarterback’s future in the hands of a know-it-all coach who was a relative novice at coaching offense was Belichick’s worst decision since benching Malcolm Butler in Super Bowl LII. Globe Staff,, 25 July 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'know-it-all.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1873, in the meaning defined above

Time Traveler
The first known use of know-it-all was in 1873

Dictionary Entries Near know-it-all

Cite this Entry

“Know-it-all.” Dictionary, Merriam-Webster, Accessed 4 Dec. 2023.

Kids Definition


: a person who always claims to know everything

More from Merriam-Webster on know-it-all

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