defective
UK: dɪˈfektɪv | US: dɪˈfɛktɪv
adj. having a defect or flaw; imperfect
adj. (law) lacking legal validity or enforceability
adj. (psychology) functioning abnormally due to mental or physical impairment
The word "defective" originates from the Latin defectus (past participle of deficere, meaning "to fail or desert"), combining de- (down, away) + facere (to do). The suffix -ive was added in Middle English via Old French to form an adjective meaning "having the quality of." Thus, "defective" literally means "having the quality of a flaw" or "prone to failure." The term evolved to describe both physical imperfections and legal/psychological inadequacies.
The factory recalled the defective products due to safety concerns.
The contract was declared defective and unenforceable by the court.
His defective vision required corrective lenses.
The psychologist studied children with defective speech development.
A defective gene was identified as the cause of the rare disease.