/ Dictionary / Index D defect: Meaning and Definition of Find definitions for: de•fect Pronunciation: (n.dē'fekt, di-fekt'v.di-fekt'), [key] — n. a shortcoming, fault, or imperfection: a defect in an argument; a defect in a machine. lack or want, esp. of something essential to perfection or completeness; deficiency: a defect in hearing. Also calleda discontinuity in the lattice of a crystal caused by missing or extra atoms or ions, or by dislocations. —v.i. to desert a cause, country, etc., esp. in order to adopt another (often fol. by from or to): He defected from the U.S.S.R to the West. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: defect (Thesaurus) defecate defection Related Content Daily Word Quiz: gregarious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language