Green’s Dictionary of Slang

split mutton n.

[SE split + mutton n. (1c)]

1. the penis.

[UK]Farmer & Henley Sl. and Its Analogues.

2. the vagina.

[UK]Farmer & Henley Sl. and Its Analogues.

3. a derog. generic term for womankind.

[UK]Farmer & Henley Sl. and Its Analogues.

In phrases