Synonyms of the word

defective

• adj. Having one or more defects.
• adj. (grammar, of a lexeme, especially a verb) lacking some forms; e.g., having only one tense or being usable…
• n. A person or thing considered to be defective.

abnormal

• adj. Not conforming to rule or system; deviating from the usual or normal type.
• adj. Of or pertaining to that which is irregular, in particular, behaviour that deviates from norms of social…
• n. A person or object that is not normal.

bad

• adj. Not good; unfavorable; negative.
• adj. Not suitable or fitting.
• adj. Seemingly non-appropriate, in manners, etc.
• adj. Unhealthy.
• adj. Tricky; stressful; unpleasant.
• adj. Evil; wicked.
• adj. Faulty; not functional.
• adj. (of food) Spoiled, rotten, overripe.
• adj. (of breath) Malodorous, foul.
• adj. (informal) Bold and daring.
• adj. (hip-hop slang) good, superlative.
• adj. (of a need or want) Severe, urgent.
• adv. (now colloquial) Badly.
• n. (slang) Error, mistake.
• n. (countable, uncountable, economics) An item (or kind of item) of merchandise with negative value; an unwanted…
• adj. (slang) Fantastic.
• v. (archaic) Alternative past tense of bid. See bade.
• v. (Britain, dialect, transitive) To shell (a walnut).

faulty

• adj. Having or displaying faults; not perfect; not adequate or acceptable.
• adj. (obsolete) At fault, to blame; guilty.

imperfect

• adj. Not perfect.
• adj. (botany) unisexual: having either male (with stamens) or female (with pistil) flowers, but not with both.
• adj. (taxonomy) Known or expected to be polyphyletic, as of a form taxon.
• adj. (obsolete) Lacking some elementary organ that is essential to successful or normal activity.
• n. Something having a minor flaw.
• n. (grammar) A tense of verbs used in describing a past action that is incomplete or continuous.
• v. (transitive) To make imperfect.

malfunctioning

• v. present participle of malfunction.
• n. A malfunction.

nonfunctional

• adj. Not functional; useless; broken.