Adjective credible has 3 senses
  1. credible, believable - capable of being believed; "completely credible testimony"; "credible information"
    Antonyms: incredible, unbelievable, astounding, dumbfounding, dumfounding, fabulous, improbable, marvelous, marvellous, tall, undreamed, undreamed of, undreamt, undreamt of, unimagined
  2. credible - a common but incorrect usage where `credulous' would be appropriate; "she was not the...credible fool he expected"
    incredulous (indirect, via credulous)
  3. credible, plausible - appearing to merit belief or acceptance; "a credible witness"; "a plausible story"
    Antonym: unconvincing (indirect, via convincing)