know-it-all

noun

Definition of know-it-allnext
as in know-all
informal + disapproving a person who talks and behaves like someone who knows everything My neighbor is a real know-it-all, always telling me what to do.

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Example Sentences

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.
Recent Examples of know-it-all Congratulations, your moment has come to be an unrepentant know-it-all on social media. — Hannah Keyser, CNN Money, 30 Jan. 2026 His electric Broadway debut as a cocky, yet vulnerable know-it-all just edged Christopher Abbott for the Should prize. — Dalton Ross, Entertainment Weekly, 29 May 2026 Dominic McLaughlin will play the Boy Who Lived, Harry Potter, while Alastair Stout plays his best friend Ron Weasley and Arabella Stanton plays know-it-all Hermione Granger. — K.j. Yossman, Variety, 10 May 2026 Here are our picks and predictions for the men’s hockey tournament, with expert analysis and critique from senior writers Sean Gentille, Mark Lazerus and James Mirtle, analytics know-it-all Shayna Goldman and goaltending expert Jesse Granger. — Shayna Goldman, New York Times, 9 Feb. 2026 See All Example Sentences for know-it-all
Recent Examples of Synonyms for know-it-all
  1. know-all
  2. wiseacre
  3. wiseass
  4. wise guy
  5. smarty
  6. smart aleck
Noun
  • How well hidden are the implications of using some other app that has an indirect path to our friendly know-all? top comment Apple's New iPhone Accessory Is Part Sock, Part Crossbody Strap 1d $150 - $230 ! ! !
    — PC Magazine, PC Magazine, 11 Nov. 2025
Definition of know-all
Noun
  • The 40-year-old singer Ryan Davis, a cowboy wiseacre with a drum machine and the patience for 11-minute anthems, riffs merrily on such existential mysteries.
    — Spencer Kornhaber, The Atlantic, 12 Dec. 2025
  • Similarly, the Pink Ladies, a popular clique headed by Rizzo (Stockard Channing), deliver their wiseacre lines with a fair dose of irony.
    — Vogue, Vogue, 10 Sep. 2024
Definition of wiseacre
Noun
  • As disarming as Rockwell is with his wry balance of doofus, savant and wiseass, and as capable as Verbinski is at keeping the brushes with death coming at a sustained pace, the movie feels most original in its flashbacks.
    — David Rooney, HollywoodReporter, 5 Feb. 2026
  • But since the emergence of a kinder, gentler Deadpool in the wiseass character’s first stand-alone movie, Wade has carried on a long-distance flirtation with Wolverine.
    — David Rooney, The Hollywood Reporter, 23 July 2024
Definition of wiseass
Noun
  • Developed by Robbins specifically for Pompeo, Chicks follows Chickie (Pompeo) and Doreen, two estranged half-sisters who are both struggling to get by when their wise guy dad unexpectedly kicks the bucket.
    — Nellie Andreeva, Deadline, 25 June 2026
  • Here’s a look at what each team in the NFC North has done in free agency, and how the wise guys in Las Vegas currently rank the division.
    — Rob Reischel, Forbes.com, 26 Mar. 2026
Definition of wise guy
Noun
  • Agnes came from a family of smarties.
    — Bea L. Hines, Miami Herald, 31 Oct. 2025
  • The suffix -y here is the same as in words like doggy or smarty, used to form nicknames or informal descriptors.
    — Erik Kain, Forbes.com, 15 Sep. 2025
Definition of smarty
Noun
  • This fuzzy, snout-nosed, smart aleck extraterrestrial whose name was Gordon Shumway crashed in the suburban garage of the Tanner family in California after escaping from the doomed planet of Melmac, which was destroyed by nuclear war.
    — Jeff Spry, Space.com, 24 Aug. 2025
  • Newton scored and so did backcourt mate Cam Spencer, that different style of smart aleck, who had 20.
    — Dom Amore, Hartford Courant, 13 June 2024
Definition of smart aleck

Browse Nearby Words

knowingness
know-it-all
know-it-alls
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Cite this Entry

“Know-it-all.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/know-it-all. Accessed 8 Jul. 2026.

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Nglish: Translation of know-it-all for Spanish Speakers

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