Excellent or very good; also a man excessively concerned with his appearance and fashionable dress.
Possibly from 'Jack Dandy' or derived from 'dandle' (to pet or fondle), though the origin is disputed. The fashion meaning emerged in the late 1700s in Britain, while the adjective meaning 'fine' came later.
Dandies were 18th and 19th century fashionistas who influenced fashion so much that men like Oscar Wilde and Lord Byron became famous as much for their clothes as for their accomplishments.
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