Green’s Dictionary of Slang

1. effeminate, exhibiting the supposed characteristics of a male homosexual; thus swishiness, homosexual characteristics.

1935		F. Wead Ceiling Zero Act II: dizzy: A right guy, that Jerry. jake: A swishy little number.
1949		‘Swasarnt Nerf’ Gaedicker’s Sodom-on-the-Hudson 2: The most friendly camaraderie between the roughest of trade and the swishiest of faggots.
1952		C. Brossard Redemption in G. Feldman (ed.) Protest (1960) 119: One of the cops imitated his swishiness much to the loud delight of his colleagues.
1958		Kerouac letter 8 Sept. in Charters II (1999) 151: Imagine huge swishy Kingsland walking into my mother’s innocent rosy kitchen.
1967		J. Rechy Numbers (1968) 56: A skinny, wonderful, unbelievably swishy old man who wore false eyelashes and a hat laden with artificial fruit.
1978		L. Kramer Faggots 179: Honey, Dame Fortune has finally smiled on this swishy schvartza.
1985		J. Wambaugh Secrets of Harry Bright (1986) 161: The bartender looked about as swishy as Rocky Marciano.
1990		(ref. to 1944) A. Bérubé Coming Out Under Fire 101: ‘We all played cards together,’ he recalled. The crowd was ‘just swishy, giddy, gay’.
2003		Nat. Post (Toronto) 15 May n.p.: You know the kind of guy I mean. A little swishy [...] Likes to drink his tea with his pinkie finger all out like this and eveything.
2012		Independent 24 Jan. 36/1: ‘Scratch a butch chef and you'll find a bitch,’ says Doonan in his typically swishy way.

2. (US gay) sexually enjoyable.

1994

G. Indiana Rent Boy 73: The bitch of it is, it’s a zillion times more swishy without the fucking condom.

3. see swish adj. (1)