a. [ L. defectivus: cf. F. défectif. See Defect. ] 1. Wanting in something; incomplete; lacking a part; deficient; imperfect; faulty; -- applied either to natural or moral qualities; as, a defective limb; defective timber; a defective copy or account; a defective character; defective rules. [ 1913 Webster ]
2. (Gram.) Lacking some of the usual forms of declension or conjugation; as, a defective noun or verb. -- De*fect"ive*ly, adv. -- De*fect"ive*ness, n. [ 1913 Webster ]
n. 1. Anything that is defective or lacking in some respect. [ Webster 1913 Suppl. ]
2. (Med.) One who is lacking physically or mentally.
☞ Under the term defectives are included deaf-mutes, the blind, the feeble-minded, the insane, and sometimes, esp. in criminology, criminals and paupers. [ Webster 1913 Suppl. ]