chuff, v.¹ — Green’s Dictionary of Slang

chuff v.¹

a euph. synon. for fuck v., in lit. and fig. senses, mainly used in the north of England.

1959		W. Hall Long and the Short and the Tall Act I: I’m going to grab a weekend off, and chuff the expense.
1977		(con. 1941) R. Beilby Gunner 139: It’s just that the old bloke’s sick so it might be better if you chuffed off.

chuff-box (n.) [box n.¹ (1) or dial. chuff, to cuff, to hit. The penis ‘hits’ the vagina during intercourse]

the vagina.

1966		Trimble 5000 Adult Sex Words and Phrases.
1980		Maledicta IV:2 (Winter) 193: The grocery, the butcher’s and the sweet shop are all represented as well as the greengrocer’s. Thus there is […] banger (a sausage, so-called because it spits when put in the oven = chuff-box).