Definition of deficient adjective from the Oxford Advanced Learner's Dictionary

     

    deficient

     adjective
    adjective
    BrE BrE//dɪˈfɪʃnt//
     
    ; NAmE NAmE//dɪˈfɪʃnt//
     
    (formal)
     
    jump to other results
  1. 1deficient (in something) not having enough of something, especially something that is essential a diet that is deficient in vitamin A Their food is deficient in iron. Your diet is deficient in iron.
  2. 2not good enough Deaf people are sometimes treated as being mentally deficient.
  3. Word Origin late 16th cent. (originally in the theological phrase deficient cause, denoting a failure or deficiency that has a particular consequence): from Latin deficient- ‘failing’, from the verb deficere ‘desert or fail’, from de- (expressing reversal) + facere ‘do’.
See the Oxford Advanced American Dictionary entry: deficient