egregious (adj.) Look up egregious at Dictionary.com
1530s, "distinguished, eminent, excellent," from Latin egregius "distinguished, excellent, extraordinary," from the phrase ex grege "rising above the flock," from ex "out of" (see ex-) + grege, ablative of grex "herd, flock" (see gregarious).

Disapproving sense, now predominant, arose late 16c., originally ironic and is not in the Latin word, which etymologically means simply "exceptional." Related: Egregiously; egregiousness.