[ dih-fish-uh nt ]
/ dɪˈfɪʃ ənt /


lacking some element or characteristic; defective: deficient in taste.
insufficient; inadequate: deficient knowledge.


a person who is deficient, especially one who is mentally defective.

Origin of deficient

1575–85; < Latin dēficient- (stem of dēficiēns, present participle of dēficere to fail, run short, lack, weaken), equivalent to dē- de- + fic-, combining form of facere to make, do1 + thematic -i- + -ent- -ent

OTHER WORDS FROM deficient Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Examples from the Web for deficient

British Dictionary definitions for deficient

/ (dɪˈfɪʃənt) /


lacking some essential; incomplete; defective
inadequate in quantity or supply; insufficient

Derived forms of deficient

deficiently, adverb

Word Origin for deficient

C16: from Latin dēficiēns lacking, from dēficere to fall short; see defect
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

Medical definitions for deficient

[ dĭ-fĭshənt ]


Lacking an essential quality or element.
Inadequate in amount or degree; insufficient.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.