Green’s Dictionary of Slang

jolly-up n.

[jolly n.1 (6)]

1. a drinking bout, a spree.

[UK]Partridge DSUE (8th edn) 627/2: from ca. 1905.

2. a good time.

[UK]Partridge DSUE (8th edn) 627/2: since early 1920s; by 1960, ob.

3. an informal dance, a party.

[US]W.R. Morse ‘Stanford Expressions’ in AS II:6 277: jolly-up — informal dance.