- a lack of something necessary for completeness or perfection; shortcoming; deficiency
- an imperfection, failing, or blemish
- (intransitive) to desert one's country, cause, allegiance, etc, esp in order to join the opposing forces
WordReference Random House Learner's Dictionary of American English © 2026
de•fect /n. ˈdifɛkt, dɪˈfɛkt; v. dɪˈfɛkt/USA pronunciation
n. [countable]
v. [no obj]
WordReference Random House Unabridged Dictionary of American English © 2026- a fault or shortcoming;
imperfection:What defect in his character made him lie?
v. [no obj]
- to desert a cause, country, etc., and go over to the opponent's side:Would the spies want to defect to the West?
de•fect
(n. dē′fekt, di fekt′;v. di fekt′),USA pronunciation n.
v.i.
de•fect′i•ble, adj.
de•fect′i•bil′i•ty, n.
de•fect′less, adj.
- 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. - CrystallographyAlso called crystal defect, lattice defect. a 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.
- Latin dēfectus failure, weakness, equivalent. to dēfec- variant stem of dēficere to run short, fail, weaken (see deficient) + -tus suffix of verb, verbal action
- late Middle English 1375–1425
de•fect′i•bil′i•ty, n.
de•fect′less, adj.
- 1. Defect, blemish, flaw refer to faults that detract from perfection. Defect is the general word for any kind of shortcoming or imperfection, whether literal or figurative:a defect in eyesight, in a plan.A blemish is usually a defect on a surface, which mars the appearance:a blemish on her cheek.Flaw is applied to a defect in quality, caused by imperfect structure (as in a diamond) or brought about during manufacture (as in texture of cloth, in clearness of glass, etc.).
Collins Concise English Dictionary © HarperCollins Publishers::
defect n /dɪˈfɛkt; ˈdiːfɛkt/
(Advertisement)
'defect' also found in these entries (note: many are not synonyms or translations):
aberration
- amnesia
- astigmatism
- blemish
- blue baby
- cast
- chromatic aberration
- cicatrize
- clean
- clear
- colour-blind
- cosmic string
- crawling
- defection
- defective
- deficient
- deformity
- fault
- flaw
- ghost
- hole in the heart
- impediment
- imperfection
- -lalia
- lallation
- lisp
- mass defect
- meltdown
- mistrial
- muscae volitantes
- -opia
- shortcoming
- spherical aberration
- spring
- taint
- tetchy
- vacancy
- varicose veins
- vice
- vicious
- vituperate
- wane
- wheel wobble
- wreath
- accuracy
- accurate
- adjustment
- alexia
- amblyopia
- aniseikonia
