know-it-all

noun

: 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
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.
After the news that the Dolphins and Pro Bowl cornerback Jalen Ramsey mutually agreed to seek a trade, some national NFL experts/know-it-alls opined the Dolphins have perhaps the worst cornerback groups in the NFL. Chris Perkins, Sun Sentinel, 25 July 2025 People seemed to engage with us as know-it-all, capital-E experts who could confidently answer any questions that were even remotely related to our specialties. Lauren Keating, Scientific American, 21 July 2025 Her uncaring parents were all too happy to have their loudmouth, know-it-all daughter off their hands. Greg Evans, Deadline, 12 June 2025 The actor played know-it-all postal worker Cliff Clavin through the series’ first nine seasons. Lauren Coates, Variety, 20 May 2025 See All Example Sentences for know-it-all

Word History

First Known Use

1873, in the meaning defined above

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

Browse Nearby Words

Cite this Entry

“Know-it-all.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/know-it-all. Accessed 29 Jul. 2025.

Kids Definition

know-it-all

noun
ˈnō-ət-ˌȯl
: a person who always claims to know everything

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