know–it–all

play
noun \ˈnō-ət-ˌȯl\

Definition of know–it–all

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

know–it–all

adjective

1873

First Known Use of know–it–all

1873


KNOW–IT–ALL Defined for English Language Learners

know-it-all

play
noun

Definition of know–it–all for English Language Learners

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


KNOW–IT–ALL Defined for Kids

know–it–all

play
noun \ˈnō-ət-ˌȯl\

Definition of know–it–all for Students

  1. :  a person who always claims to know everything


Learn More about know–it–all


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