a person who has no opinion or is undecided, as in answering an item on a public-opinion poll.

Nearby words

  1. don't mention it,
  2. don't put all your eggs in one basket,
  3. don't put off,
  4. don't put the cart before the horse,
  5. don't throw out the baby with the bath water,
  6. dona,
  7. donable,
  8. donald,
  9. donar,
  10. donate

Origin of don't-know

First recorded in 1885–90 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for don't know

don't know


a person who has not reached a definite opinion on a subject, esp as a response to a questionnaire
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012