know-noth·​ing | \ ˈnō-ˌnə-thiŋ \

Definition of know-nothing

1a : ignoramus
b : agnostic
2 capitalized K&N : a member of a 19th century secret American political organization hostile to the political influence of recent immigrants and Roman Catholics

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know-nothing adjective

Synonyms & Antonyms for know-nothing


airhead, birdbrain, blockhead, bonehead, bubblehead, chowderhead, chucklehead, clodpoll (or clodpole), clot [British], cluck, clunk, cretin, cuddy (or cuddie) [British dialect], deadhead, dim bulb [slang], dimwit, dip, dodo, dolt, donkey, doofus [slang], dope, dork [slang], dullard, dum-dum, dumbbell, dumbhead, dummkopf, dummy, dunce, dunderhead, fathead, gander, golem, goof, goon, half-wit, hammerhead, hardhead, idiot, ignoramus, imbecile, jackass, knucklehead, lamebrain, loggerhead [chiefly dialect], loon, lump, lunkhead, meathead, mome [archaic], moron, mug [chiefly British], mutt, natural, nimrod [slang], nincompoop, ninny, ninnyhammer, nit [chiefly British], nitwit, noddy, noodle, numskull (or numbskull), oaf, pinhead, prat [British], ratbag [chiefly Australian], saphead, schlub (also shlub) [slang], schnook [slang], simpleton, stock, stupe, stupid, thickhead, turkey, woodenhead, yahoo, yo-yo


brain, genius

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First Known Use of know-nothing

1812, in the meaning defined at sense 1a

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Time Traveler for know-nothing

The first known use of know-nothing was in 1812

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English Language Learners Definition of know-nothing

: a person who lacks intelligence or knowledge : a stupid or ignorant person

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irregularly rounded

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