Green’s Dictionary of Slang

pikestaff n.

the penis.

1691		‘The Tinker of Turvey’ in Ebsworth Merry Drollery Compleat (1875) 28: He walks about th Country, / With Pikestaff and with Butchet.
1890–1904		Farmer & Henley Sl. and Its Analogues.
1896		Farmer Vocabula Amatoria (1966) 212: Pique, f. The penis; ‘the pike-staff’.
1980		Maledicta IV:2 (Winter) 194: Weaponry is particularly well represented [...] for length (pikestaff).