Green’s Dictionary of Slang

1. a man about town.

1895		Coburg Leader (Vic.) 29 June 1/6: Who was the gussie that had a mortgage on the Sydney-road Sunday night with his donah? Ask Rogie.
1901		Sydney Sportsman (Surry Hills, NSW) 28 Aug. 1/4: Here, every Sunday, can be seen the gussies and Berties of Society.
1904		H.M. Watkins [perf. Mark Sheridan] ‘All the little ducks went quack, quack, quack’ 🎵 Gussie was a gilded youth sitting in the stalls.
1907		Sun. Times (Perth) 3 Mar. 1/1: A certain Fremantle Bank gussie is going altogether too strong [and] three tarts at a time is over his limit.
1910		Rogers & Powell [perf. Marie Lloyd] Are You Looking for a Girl Like Me? 🎵 There’s a chappie in the stalls, nice boy! I don't flatter! / He’s been looking round like mad, / Gussie, what's the matter?’.

2. (Aus./US) a weak, effeminate man; thus a male homosexual.

1901		Sydney Sportsman (Surry Hills, NSW) 25 Sept. 1/3: Young men that are poor must not indulge in any pastime on a Sunday, but the well-to-do Miss Nancys may, and do [...] No summoning of these Gussies.
1902		Ade Forty Modern Fables 46: The Husband that she had set up as a Shining Example was a feather-brained Gussie, who ought to be Drummed Out of the Community.
1914		Truth (Melbourne) 10 Jan. 11/4: Sometimes [i.e. young women] they are accompanied by Gussie, towel in hand and his boiled shirt open in front.
1924		Townsville Daily Bulletin (Qld) 22 Nov. 4s/3: A sickly smile drifted across the gussie’s face.
1928		Hecht & MacArthur Front Page Act II: How’s your gussie mollie?
1941		Baker Popular Dict. Aus. Sl. 33: Gussie, an effeminate or affected man.
1955		N. Pulliam I Travelled a Lonely Land (1957) 139: Tell ’em you hear Aussie Rules are just for gussies and poor wets.
1999		(ref. to 1890s) G. Seal Lingo 115: Later in the l9th century came the term gussie and the 20th century has contributed many more.