Green’s Dictionary of Slang

gutstick n.

the penis.

[UK]Farmer & Henley Sl. and Its Analogues.
[UK]Farmer Vocabula Amatoria (1966) 35: Béquille du père Barnaba (la). The penis; ‘the gut-stick’.
[US]R. Klein Jailhouse Jargon and Street Sl. [unpub. ms.].
[UK]Roger’s Profanisaurus 3 in Viz 98 Oct. 5: boh exclam. The noise made by a man after a particularly heavy woman has bounced up too far and sat down hard on his gut-stick, breaking it in two. Reportedly Prince Albert’s last word.

In phrases