Green’s Dictionary of Slang

1. (Aus./UK society, also Cinderella dance, ...social) a dance that ends at midnight.

1883		Standard 8 Jan. 5/2: The ‘Cinderella dance’ is much affected .
1887		Bulletin (Sydney) 15 Oct. 12/1: What man was ever known to propose or even give indications of being mildly interested in his partner at a liquorless ‘Cinderella?’.
1890		Bulletin (Sydney) 12 July 6/3: A ‘Cinderella’ dance, got up by a few of the professional musicians of Sydney, will be held on the 15th instant at West’s rooms.
1894		Daily News 27 Mar. in Ware (1909) 77/2: The hours at which balls begin grow later and later. The stroke which sends the last guest hurrying away from the Cinderalla dance scarcely ushers the first arrival to a season ball.
1896		Riverina Recorder (Moulamein, NSW) 24 June 2/4: [W]e certainly want something to while away the long winter nights [...] a Cinderella. Social would be a good idea.
1902		H. Champion ‘It Won’t Last Very Very Long’ [monologue] One fine night I toddled to a dance, what the people call a ‘cinderella’.

2. (US gay) an older homosexual who both looks better by candlelight and has to be home by midnight.

1972		B. Rodgers Queens’ Vernacular 46: Cinderella [Cindy] (camp) 1. burly-framed man who acts years younger than his peers; one who looks better at night (by candlelight) 2. older queen who has to be in by twelve before her face falls off 3. (kwn LV, mid ’60s) young, gay gadabout; a silly effeminate.
2003		K. Cage Gayle 62/1: Cinderella n. someone who looks better at night, preferably in subdued lighting.