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know better

idiom

Definition of know better

1 : to be smart or sensible enough not to do something
  • You walked home alone? Don't you know better (than that)?
  • She'll know better than to trust them again.
  • There's no excuse for his behavior. He's old enough to know better.
  • Don't blame him. He's just a child and he doesn't know (any) better.
2 : to know or understand the truth about something
  • She tried to tell me that it wasn't her fault, but I know better.
3 : to know or understand more than other people
  • You can't tell him what to do. He always thinks that he knows better.

Word by Word Definitions

know play

  1. : to perceive directly : have direct cognition of

  2. : to have understanding of

  3. : to recognize the nature of : discern

  1. : knowledge

See the full definition of know
better play

  1. : comparative of good

  2. : greater than half

  3. : improved in health or mental attitude

  1. : to make better (see 1better): such as

  2. : to make more tolerable or acceptable

  3. : to make more complete or perfect

  1. : comparative of well

  2. : in a more excellent manner

  3. : to greater advantage : preferably

  1. : something better (see 1better)

  2. : a superior especially in merit or rank

  3. : advantage, victory

  1. : had better (see 3better 1b)

See the full definition of better

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