know all

/ˈnoʊ ɔl/
noun
  1. A person who acts as if they know everything, often in an annoying way.
    • Nobody likes a know-all who never admits they're wrong.
    • She's a bit of a know-all, but she actually does know a lot.
    • Our new coworker is such a know-all — he corrects everyone's mistakes.
Synonyms
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