faultless

adjective

1 he replied in faultless English:

perfect, flawless, without fault, error-free, without blemish, unblemished, impeccable, accurate, precise, exact, correct, unerring;

exemplary, model, ideal, copybook, scrupulous, meticulous, just so;

British, informal spot on, bang on, on the mark, on the nail, on the button.

▷antonyms flawed, faulty.

2 the wife of the prisoner was faultless:

guiltless, without guilt, innocent, blameless, above reproach, irreproachable, sinless, pure, unsullied.

▷antonyms guilty.

faultless Oxford Dictionary of English