Deficient \De*fi"cient\, a. [L. deficiens, -entis, p. pr. of deficere to be wanting. See Defect.]

Wanting, to make up completeness; wanting, as regards a requirement; not sufficient; inadequate; defective; imperfect; incomplete; lacking; as, deficient parts; deficient estate; deficient strength; deficient in judgment.

The style was indeed deficient in ease and variety. --Macaulay.

Deficient number. (Arith.) See under Abundant. -- De*fi"cient-ly, adv.

Source: Webster's Revised Unabridged Dictionary (1913)