defective

1 of 2

adjective

de·​fec·​tive di-ˈfek-tiv 

1

a

: having a defect or flaw : imperfect in form, structure, or function

replaced a defective light switch

products manufactured with defective materials

defective intestinal absorption

a defective gene

b

dated, now offensive : having a physical or mental impairment

2

grammar : lacking one or more of the usual forms of inflection (see inflection sense 2)

Must is a defective verb.

defectively adverb

defectiveness noun

defective

2 of 2

noun

1

: something that is imperfect in form, structure, or function

… if we examine 18 items off the production line, we may be interested in the number of defectives we observe …

—Lloyd Jaisingh

2

dated, now offensive : a person having a physical or mental impairment

Synonyms of defective

Adjective

• imperfect
• bad
• flawed
• faulty
• damaged
• broken

Examples of defective in a Sentence

Adjective

This computer is defective. I want my money back.

The disease is caused by a defective gene.

Recent Examples on the Web

Adjective

Multiple photos of the same complex’s ruins following the earthquakes show that at least some of those defective stirrups were never rectified, experts said. — Avery Schmitz, CNN Money, 8 Nov. 2026

Consider a hypothetical evaluation containing 990 acceptable parts and 10 defective ones. — Rajesh Iyengar, Forbes.com, 5 Nov. 2026

Neither of these defective filings provides a basis on which the Court could give its approval. — Dominic Patten, Deadline, 28 Oct. 2026

Some customers have reported success taking their defective phones to Apple stores for replacement, but spares may be in short supply right now. — Ryan Whitwam, ArsTechnica, 27 Oct. 2026

Word History

Etymology

Adjective

Middle English defectif, defectyve "lacking, faulty, of poor quality," borrowed from Anglo-French defectif, borrowed from Late Latin dēfectīvus "lacking an inflectional form, imperfect, faulty," from Latin dēfectus, past participle of dēficere "to be lacking, run short, fail" + -īvus -ive — more at deficient

Noun

derivative of defective entry 1

First Known Use

Adjective

14th century, in the meaning defined at sense 1a

Noun

1562, in the meaning defined at sense 1

Rhymes for defective

• advective
• affective
• collective
• connective
• convective
• corrective
• detective
• directive
• effective
• elective
• infective
• injective

Kids Definition

defective

adjective

de·​fec·​tive

di-ˈfek-tiv

: lacking something essential : faulty

defective brakes

defectively adverb

defectiveness noun

Medical Definition

defective

adjective

de·​fec·​tive di-ˈfek-tiv 

: falling below the norm in structure or function

a defective heart valve

defectiveness

-nəs 

noun