1.
[syn: faultless, immaculate, impeccable]
2. not capable of sin;
The Collaborative International Dictionary of English v.0.48:
Impeccable \Im*pec"ca*ble\, a. [L. impeccabilis; pref. im- not +
peccare to err, to sin: cf. F. impeccable.]
Not liable to sin; exempt from the possibility of doing
wrong. -- n. One who is impeccable; esp., one of a sect of
Gnostic heretics who asserted their sinlessness.
[1913 Webster]
God is infallible, impeccable, and absolutely perfect.
--P. Skelton.
[1913 Webster]
WordNet (r) 3.0 (2006):
impeccable
adj 1: without fault or error; "faultless logic"; "speaks
impeccable French"; "timing and technique were
immaculate"; "an immaculate record" [syn: faultless,
immaculate, impeccable]
2: not capable of sin