Green’s Dictionary of Slang

date n.3

[rhy. sl.; date and plum = bum n.1 (1); note 17C dog-date, dog excrement, from supposed resemblance]

1. [1910s+] (Aus./N.Z./UK) the anus, the backside as a whole.

2. [1910s] (Aus.) a term of abuse [f. sense 1].

In compounds

date puncher (n.) (also date-driller, ...packer)

[1980s+] (Aus.) a male homosexual.

date roll (n.)

[1980s] a roll of lavatory paper.