1) Beyond reproach 2) Faultless 3) Flawless 4) French word used in English 5) Immaculate 6) Incapable of sin 7) Not capable of sin 8) Not liable to sin 9) Perfect 10) Without fault or error 1) Blameless 2) Faultless 3) Ideal 4) Perfect 
• (n.) One who is impeccable; esp., one of a sect of Gnostic heretics who asserted their sinlessness. • (a.) Not liable to sin; exempt from the possibility of doing wrong.
Not liable to sin; exempt from the possibility of doing wrong. ... One who is impeccable; especially, one of a sect of Gnostic heretics who asserted their sinlessness. 'God is infallible, impeccable, and absolutely perfect.' (P. Skelton) ... Origin: L. Impeccabilis; pref. Im- not + peccare to err, to sin: cf. F. Impeccable. ... Source: Websters Dic...
Im·pec'ca·ble adjective [ Latin impeccabilis ; prefix im- not + peccare to err, to sin: confer French impeccable .] Not liable to sin; exempt from the possibility of doing wrong. -- noun One who is impeccable; esp., one of a sect of Gnostic heretic...
The USS Impeccable was an American Auk Class minesweeper of 890 tons displacement launched in 1943. The USS Impeccable was powered by diesel engines providing a top speed of 18 knots and carried a complement of 105. She was armed with one 3 inch dual-purpose gun and two 40 mm anti-aircraft guns.
[adj] - not capable of sin
impeccable, impeccability, impecably 1. So perfect or flawless as to be beyond criticism. 2. So perfect in character as to be incapable of sinning.
adjective not capable of sin
faultless; flawless; irreproachable: impeccable manners. · not liable to sin; incapable of sin.