Green’s Dictionary of Slang

an inadequate person, a weakling.

1997–2001		Online Sl. Dict. 🌐 limpdick n 1. a coward or non-violent person or either sex. (‘Crash is a real limpdick.’).
2013		S. Barber ‘Killer, Duck and The Boys’ in ThugLit Apr. [ebook] ‘Our anniversary is tomorrow and you limp dicks already fucked it up’ .
2017		T. Pluck Bad Boy Boogie [ebook] ‘Limp dicks at do-nothing jobs’.