: lacking in style or good taste : vulgar and unfashionable
I was going to get a pair of leather jeans as well, but it was too expensive and anyway, leather pants look naff, as I discovered later. Melvin Burgess, Smack, 1996
… the terrifying door girl Scarlett sat guard and held up a hand mirror to anyone she considered too naff to enter, with the withering line "Would you let yourself in?" Hamish Bowles, Vogue, November 2012
Word History
Etymology
perhaps borrowed from Polari (English argot used by theatrical and circus performers and in certain gay subcultures, derived in part from Italian); ulterior origin uncertain
Note: A summary of hypotheses on the origin of naff can be found in the Oxford English Dictionary, on-line third edition (this entry updated June, 2003). The putative Polari phrase naff omi "a dreary man," unattributed in the Oxford etymology, is apparently from a communication by the comic actor Kenneth Williams, in 1980, to Paul Beale, the editor of Eric Partridge's A Dictionary of Slang and Unconventional English, 8th edition, 1984 (see p. 775).