Green’s Dictionary of Slang

(US) sophisticated; smart; well-dressed.

1902		C.L. Cullen More Ex-Tank Tales 47: He didn’t want to mingle with the downtown population.
1942		L. Bennett ‘Strike Day’ Jamaica Dialect Verses 26: We tun out all de dung-tung man / An’ ’oman from dem store.
1954		Hepster’s Dict. 9: Real down town – Excellent.
1964		‘Pimping Sam’ in D. Wepman et al. Life (1976) 147: I said, ‘I didn’t mean to step on your toes, / But I thought you was one of them downtown whores.’.
1971–2		C. Shafer ‘Catheads [...] and Cho-Cho Sticks’ in Abernethy Bounty of Texas (1990) 203: downtown stud, n. – a sharp, well-dressed man.
1973		A. Salkey ‘Saturday in Kingston’ Jamaica (1983) 57: A downtown gal / rolled her hips [...] the sidewalk / slipped away unnoticed, / under her vaseline smooth / patent-leather shoes, / as sidewalks should / under a downtown girl.
1993		(con. 1969) N.L. Russell Suicide Charlie 94: The sappers could stroll through triple rows of concertina wire like a downtown dude cruising for chicks, and they were just as likely to score.