IMPECCABLY
impeccably
(adverb) flawlessly; “the film was impeccably authentic”
Source: WordNet® 3.1
Etymology
Adverb
impeccably (comparative more impeccably, superlative most impeccably)
In a perfect or flawless manner.
Synonyms
• (in a perfect manner): flawlessly, immaculately, perfectly
Source: Wiktionary
IMPECCABLE
Im*pec"ca*ble, a. Etym: [L. impeccabilis; pref. im- not + peccare to
err, to sin: cf. F. impeccable.]
Definition: Not liable to sin; exempt from the possibility of doing wrong.
– n.
Definition: One who is impeccable; esp., one of a sect of Gnostic heretics
who asserted their sinlessness.
God is infallible, impeccable, and absolutely perfect. P. Skelton.
Source: Webster’s Unabridged Dictionary 1913 Edition