Synonyms for Impeccable:

adj.

above suspicion; flawless (adjective)
infallible, irreproachable, immaculate, unflawed, pure, faultless, perfect.
innocent (adjective)
irreproachable.
perfect (adjective)
flawless, faultless, perfect, unspoiled, acme, ultimate, Indefectible, unflawed, consummate, Taintless, letter-perfect, complete.

n.

infallible, irreproachable, watertight, above/beyond reproach, pure, model, ideal, excellent, ideally, perfectly. good, Indefectible, unflawed, absolute. impeccable (noun)
immaculate, virtuous, perfect, faultless.

Other synonyms:

watertight, Indefectible, irreproachable, ideally, unflawed. infallible, perfectly. absolute. model. Other relevant words:
ideally, absolute, ideal, model, immaculate, infallible, good, unflawed, excellent, virtuous, perfectly, Indefectible, irreproachable, pure.

Usage examples for impeccable

  1. Her demeanour could not have been more impeccable had she been trained in a French convent. – The Morals of Marcus Ordeyne by William J. Locke