from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun One who claims to know everything and rejects others' advice or information.

from the GNU version of the Collaborative International Dictionary of English.

  • noun Colloq. & pejorative, Colloq. & pejorative, Colloq. & pejorative One who knows everything

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun pejorative Someone who obnoxiously claims to be knowledgeable on a subject.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun someone who thinks he knows everything and refuses to accept advice or information from others


Sorry, no etymologies found.


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