Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

swear by

Definition of swear by

  1. :  to have or express a lot of confidence in (something) :  to say that (something) is very good or useful <She swears by this diet.>



Word by Word Definitions

swearplay
  1. :  to utter or take solemnly (an oath)

    :  to assert as true or promise under oath

    :  to assert or promise emphatically or earnestly

  1. :  oath, swearword


Seen and Heard

What made you want to look up swear by? Please tell us where you read or heard it (including the quote, if possible).