In a manner showing complete interest and attention; done with fascination or deep engagement.
From fascinate (to hold attention as if by magic) + -ed (past participle adjective) + -ly (adverb marker). Fascinate comes from Latin fascinare (to bewitch), from fascinum (spell or evil eye).
The original sense of 'fascinate' comes from the idea of being 'bewitched' by an evil eye, which is why we still say someone can hold us 'spellbound'—the magical imagery stuck around even though we don't believe in actual spells anymore.
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