In a way that causes physical pain, or in a way that is distressing, awkward, or embarrassing.
From 'painful' (causing pain), derived from 'pain' (from Latin 'poena' meaning punishment or suffering) plus the adverb suffix '-ly.'
The word 'painfully' is one of the few English adverbs that can describe emotional rather than physical pain—'painfully shy' or 'painfully obvious'—showing how psychology and language intertwine.
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