Green’s Dictionary of Slang

flossy adv.

[flossy adj. (1)]

attractively, smartly.

[US]S. Ford Shorty McCabe on the Job 66: ‘That does listen flossy,’ says I. [Ibid.] 67: If they’re young and flossy dressed, he calls ’em ‘fluffs’; but anything over twenty-five, no matter how she’s costumed, is a lady.