English egregious descends from Latin egregius, literally 'out of the flock' (ex + grex), which originally signified the highest distinction before ironic usage across the sixteenth and seventeenth centuries permanently inverted its polarity from supreme praise to emphatic condemnation — one of the most complete semantic reversals on record.
Originally meaning 'standing out from the flock' (Latin ē- 'out of' + grex 'flock'), now denoting something outstandingly bad or shocking, having undergone a complete semantic inversion from its earlier sense of 'remarkably good'.
Egregious derives from Latin egregius, meaning 'illustrious, distinguished, excellent,' literally 'standing out from the flock.' It is a compound of the prefix ex- ('out of') and grex (genitive gregis), meaning 'flock, herd.' The word entered English in the mid-16th century retaining its positive Latin sense: someone egregious was remarkably talented or eminent. Writers like Sir Thomas More used it approvingly. However, by the late 16th and early 17th centuries, the word underwent one of the most dramatic semantic reversals (called pejoration) in English. It began appearing in ironic contexts — 'an egregious liar' meant someone who stood out for their dishonesty. The ironic usage gradually eclipsed
When Shakespeare wrote 'egregious' his audiences had to judge from context alone whether he meant brilliant or terrible, because the word was mid-reversal during his lifetime — functioning as genuine praise in some passages and biting sarcasm in others. By 1700 the positive meaning had vanished entirely. The structural irony is that 'standing out from the flock' carries no built-in direction, so the same Latin shepherd's metaphor that Romans used to honour their finest generals is now reserved for the worst blunders imaginable. Every modern use still performs