Green’s Dictionary of Slang

1. to sodomize; thus bumfucking n., sodomy.

1879		‘Nursery Rhymes’ in Pearl 4 Oct. 34: His chere amie, who prefers bum-fucking to the old orthodox plan of coition.
1888–94		‘Walter’ My Secret Life (1966) VIII 1569: She didn’t hesitate to say she would like to be bum-fucked again.
c.1900		‘Ramrod’ Family Connections 50: Occasionally there was some bum-fucking [...] performed with great satisfaction by the boys [...] piercing a grown-up woman‘s great arse.
1967		J. Orton Diaries (1986) 28 July 260: Just across the border there’s poverty and bum-fucking.
1975		Ribald (Sydney) 3 Apr. 4/3: Bum fucking is my favourite sex says Greek IMIGRANT [sic] Fina, who now lives in the Sydney suburb of Yagoona.
1989–2003		R.O. Scott Gay Sl. Dict. 🌐 anal intercourse: [...] Syn: bum fuck.
1996		Vertigo (Sydney) #3 12/1: Anal intercourse: buggery, sodomy, arse-fucking, bum-fucking.
2004		Harvard Indep. 14 Oct. 🌐 Despite the positive press and numerous porn sites devoted to the ancient art of bumfucking (RectalRooter.com, anyone?), anal still manages to get a bad rap from the uninformed.

2. (orig. US) to massage the prostate as a way of diagnosing and treating gonorrhoea.

1984

Partridge DSUE (8th edn) 154/1: C.20.