FAULTY
faulty, incorrect, wrong
(adjective) characterized by errors; not agreeing with a model or not following established rules; “he submitted a faulty report”; “an incorrect transcription”; “the wrong side of the road”
defective, faulty
(adjective) having a defect; “I returned the appliance because it was defective”
Source: WordNet® 3.1
Etymology
Adjective
faulty (comparative faultier, superlative faultiest)
Having or displaying faults; not perfect; not adequate or acceptable.
(obsolete) At fault, to blame; guilty.
Usage notes
• Nouns to which "faulty" is often applied: goods, equipment, product, wiring, construction, memory, thinking, design, hardware, software, unit, part, component, assumption, reasoning, premise, gene, operation, technique, merchandise, circuit, code, analysis, posture, machine, method, habit, process, communication.
Antonyms
• faultless
Source: Wiktionary
Fault"y, a.
1. Containing faults, blemishes, or defects; imperfect; not fit for
the use intended.
Created once So goodly and erect, though faulty since. Milton.
2. Guilty of a fault, or of faults; hence, blamable; worthy of
censure. Shak.
The king doth speak . . . as one which is faulty. 2 Sam. xiv. 13.
Source: Webster’s Unabridged Dictionary 1913 Edition