know-it-all

Australia/ˈnəʉ.ɪt.oːl/

noun

Someone who claims to be knowledgeable or an expert in something, obnoxiously dismissing the opinions, advice, suggestions, etc. of others.

“We had it all figured out, but this know-it-all marched in with "the correct way of solving it", leaving our experiment in shambles.”

Similar
Buddhaclever clogsclever dickknow-allsmart alecksmart asssmartysmarty pants
Opposite
wise person
OriginEnglish all ← Middle English all ← Old English eall →
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Meanings

nounknow-it-all (plural know-it-alls)

plural know-it-alls · alternative Commonwealth Ireland UK know-all

  1. USderogatorySomeone who claims to be knowledgeable or an expert in something, obnoxiously dismissing the opinions, advice, suggestions, etc. of others.

    We had it all figured out, but this know-it-all marched in with "the correct way of solving it", leaving our experiment in shambles.

    3 more examples

    The same holds true for supporting details—they help you to learn more about a topic. Be a know it all by sharing these details and supporting details with friends.

    2004, Princeton Review, Know It All! Grades 9-12 Reading, The Princeton Review, →ISBN, page 22

    She's a mean, bossy know-it-all.

    2005, Pansie Hart Flood, Tiger Turcotte Takes on the Know-it-all, Carolrhoda Books, →ISBN

    Have you ever gone shopping with a Know-It-All girlfriend and she insists, without your consent or consulting you first, to choose your outfits for you?

    2012, Joe Ike, How do I relate with a “know-it-all”?, xBusinessServices Corp., page 60

    Synonyms: Buddha, clever clogs, clever dick, know-all, smart aleck, smart ass, smarty, smarty pants

Synonyms & antonyms

nounSomeone who claims to be knowledgeable or an expert in something, obnoxiously dismissing the opinions, advice, suggestions, etc. of others.

Similar
Buddhaclever clogsclever dickknow-allsmart alecksmart asssmartysmarty pantswiseacrewiseasswise-asswisenheimer
Opposite
wise person

More synonyms by meaning

nounsomeone who thinks they know everything and refuses to accept advice or information from others

Similar
know-all
Broader
egotistegoistswellhead
Also see
clever clogsclever dickeinsteinknow-allknow-everythingsciolistsmart alecksmart arsesmart asssmartasssmartysmarty pantswiseacrewise guywisenheimer

Synonym sets from Open English WordNet, CC BY 4.0.

Origin

  1. Proto-Indo-European*ǵneh₃-
  2. Proto-Germanic*knēaną
  3. Proto-West Germanic*knāan
  4. Old Englishcnāwan
  5. Middle Englishknowen
  6. Englishknow
  7. Englishit
  8. Proto-Indo-European*h₂el-der.?
  9. Proto-Indo-European*h₂elnós
  10. Proto-Germanic*allaz
  11. Proto-West Germanic*all
  12. Old Englisheall
  13. Middle Englishall
  14. Englishall
  15. Englishknow-it-all

From know + it + all.

Full word history & related roots →

Translations

Arabic مُتَعَالِم
  • مُتَعَالِم (mutaʕālim)one who obnoxiously claims to be knowledgeable on a subject
Basque sasijakintsu, sasijakitun
  • sasijakintsuone who obnoxiously claims to be knowledgeable on a subject
  • sasijakitunone who obnoxiously claims to be knowledgeable on a subject
Bulgarian всезнайко
  • всезнайко (vseznajko)one who obnoxiously claims to be knowledgeable on a subject
Catalan setciències, mestretites
  • setciènciesone who obnoxiously claims to be knowledgeable on a subject
  • mestretitesone who obnoxiously claims to be knowledgeable on a subject
Chinese Mandarin 萬事通 /万事通
  • 萬事通 /万事通 (wànshìtōng)one who obnoxiously claims to be knowledgeable on a subject
Czech vševěd, rozumbrada
  • vševědone who obnoxiously claims to be knowledgeable on a subject
  • rozumbradaone who obnoxiously claims to be knowledgeable on a subject
Danish klogeåge, besserwisser
  • klogeågeone who obnoxiously claims to be knowledgeable on a subject
  • besserwisserone who obnoxiously claims to be knowledgeable on a subject
Dutch betweter, wijsneus
  • betweterone who obnoxiously claims to be knowledgeable on a subject
  • wijsneusone who obnoxiously claims to be knowledgeable on a subject
Finnish kaikkitietävä, besserwisser
  • kaikkitietäväone who obnoxiously claims to be knowledgeable on a subject
  • besserwisserone who obnoxiously claims to be knowledgeable on a subject
French je-sais-tout, ti-Jo Connaissant
  • je-sais-toutone who obnoxiously claims to be knowledgeable on a subject
  • ti-Jo Connaissantone who obnoxiously claims to be knowledgeable on a subject
  • toutologueone who obnoxiously claims to be knowledgeable on a subject
German Besserwisser, Besserwisserin
  • Besserwisserone who obnoxiously claims to be knowledgeable on a subject
  • Besserwisserinone who obnoxiously claims to be knowledgeable on a subject
  • Neunmalklugerone who obnoxiously claims to be knowledgeable on a subject
  • Neunmalklugeone who obnoxiously claims to be knowledgeable on a subject
  • Rechthaberone who obnoxiously claims to be knowledgeable on a subject
  • Rechthaberinone who obnoxiously claims to be knowledgeable on a subject
  • Schulmeisterone who obnoxiously claims to be knowledgeable on a subject
  • Schulmeisterinone who obnoxiously claims to be knowledgeable on a subject
  • Klugscheißerone who obnoxiously claims to be knowledgeable on a subject
  • Klugscheißerinone who obnoxiously claims to be knowledgeable on a subject
  • Schlaumeierone who obnoxiously claims to be knowledgeable on a subject
  • Schlaumeierinone who obnoxiously claims to be knowledgeable on a subject
Greek ξερόλας, ξερόλα
  • ξερόλας (xerólas)one who obnoxiously claims to be knowledgeable on a subject
  • ξερόλα (xeróla)one who obnoxiously claims to be knowledgeable on a subject
Indonesian sok pintar, sok tau
  • sok pintarone who obnoxiously claims to be knowledgeable on a subject
  • sok tauone who obnoxiously claims to be knowledgeable on a subject
Italian sapientone, sa tutto
  • sapientoneone who obnoxiously claims to be knowledgeable on a subject
  • sa tuttoone who obnoxiously claims to be knowledgeable on a subject
  • saputelloone who obnoxiously claims to be knowledgeable on a subject
  • tuttologoone who obnoxiously claims to be knowledgeable on a subject
  • nientologoone who obnoxiously claims to be knowledgeable on a subject
Japanese 知ったかぶりをする人
  • 知ったかぶりをする人 (shittakaburi o suru hito)one who obnoxiously claims to be knowledgeable on a subject
Malay palatao
  • palataoone who obnoxiously claims to be knowledgeable on a subject
Māori whakaputa mōhio, ngutu huia
  • whakaputa mōhioone who obnoxiously claims to be knowledgeable on a subject
  • ngutu huiaone who obnoxiously claims to be knowledgeable on a subject
Norwegian Bokmål bedreviter, viktigper
  • bedreviterone who obnoxiously claims to be knowledgeable on a subject
  • viktigperone who obnoxiously claims to be knowledgeable on a subject
  • forståsegpåerone who obnoxiously claims to be knowledgeable on a subject
  • besserwisserone who obnoxiously claims to be knowledgeable on a subject
Persian علامه دهر
  • علامه دهر ('allâme-ye dahr)one who obnoxiously claims to be knowledgeable on a subject
Polish przemądrzalec, mądraliński
  • przemądrzalecone who obnoxiously claims to be knowledgeable on a subject
  • mądralińskione who obnoxiously claims to be knowledgeable on a subject
  • mądralińskaone who obnoxiously claims to be knowledgeable on a subject
  • mądralaone who obnoxiously claims to be knowledgeable on a subject
  • chłopek-roztropekone who obnoxiously claims to be knowledgeable on a subject
  • besserwisserone who obnoxiously claims to be knowledgeable on a subject
  • zarozumialecone who obnoxiously claims to be knowledgeable on a subject
Portuguese sabichão, sabichona
  • sabichãoone who obnoxiously claims to be knowledgeable on a subject
  • sabichonaone who obnoxiously claims to be knowledgeable on a subject
  • sabe-tudoone who obnoxiously claims to be knowledgeable on a subject
Russian всезна́йка, зна́йка
  • всезна́йка (vseznájka)one who obnoxiously claims to be knowledgeable on a subject
  • зна́йка (znájka)one who obnoxiously claims to be knowledgeable on a subject
Spanish sabelotodo, sabiondo
  • sabelotodoone who obnoxiously claims to be knowledgeable on a subject
  • sabiondoone who obnoxiously claims to be knowledgeable on a subject
  • todólogoone who obnoxiously claims to be knowledgeable on a subject
  • cuñadoone who obnoxiously claims to be knowledgeable on a subject
  • cerebrutoone who obnoxiously claims to be knowledgeable on a subject
  • sabidilloone who obnoxiously claims to be knowledgeable on a subject
Swahili mjuba
  • mjubaone who obnoxiously claims to be knowledgeable on a subject
Swedish viktigpetter, besserwisser
  • viktigpetterone who obnoxiously claims to be knowledgeable on a subject
  • besserwisserone who obnoxiously claims to be knowledgeable on a subject
Tagalog dunong-dunungan
  • dunong-dununganone who obnoxiously claims to be knowledgeable on a subject
Turkish çok bilmiş, herbokolog
  • çok bilmişone who obnoxiously claims to be knowledgeable on a subject
  • herbokologone who obnoxiously claims to be knowledgeable on a subject
Ukrainian всезна́йко
  • всезна́йко (vseznájko)one who obnoxiously claims to be knowledgeable on a subject
Welsh hollwybodusyn
  • hollwybodusynone who obnoxiously claims to be knowledgeable on a subject
Cite this entry
APA

know-it-all. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/know-it-all

MLA

“know-it-all.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/know-it-all. Accessed November 2, 2026.

Chicago

WatkinsX Dictionary, s.v. “know-it-all,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/know-it-all.

Source: know-it-all on Wiktionary, CC BY-SA 4.0.