know–it–all

noun \ˈnō-ət-ˌȯl\

: a person who talks and behaves like someone who knows everything

Full Definition of KNOW-IT-ALL

: one who claims to know everything; also : one who disdains advice

— know–it–all adjective

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See know-it-all defined for kids

1895

KNOW-IT-ALL Defined for Kids

noun \ˈnō-ət-ˌȯl\

: a person who always claims to know everything

Next Word in the Dictionary: knowledgablePrevious Word in the Dictionary: knowing All Words Near: know-it-all

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