defective

(noun, adjective)

adjective

1. having a defect

- I returned the appliance because it was defective

Similar word(s): imperfect, faulty

2. markedly subnormal in structure or function or intelligence or behavior

- defective speech

Similar word(s): abnormal, unnatural

3. not working properly

- a defective appliance

Similar word(s): malfunctioning, nonfunctional, bad

noun

1. A person or thing considered to be defective.