Dictionary.com
definitions
  • synonyms

know-it-all

[noh-it-awl]
See more synonyms on Thesaurus.com
noun
  1. a person who acts as though he or she knows everything and who dismisses the opinions, comments, or suggestions of others.
Show More
adjective
  1. of or characteristic of a know-it-all.
Show More

Origin of know-it-all

First recorded in 1930–35
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Idioms and Phrases with know it all

know it all

see know all the answers.

Show More
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.