The really poor excuse for an erection that all men will almost invariably try to put into effect after an overly beery night out (or in if you're a loser).

Usually ends up exposed and marker penned by so-called mates when you finally pass out and lack the capacity or care to put it away.
Tom had throughly shit sex as he had a drunken jelly sword and could not achieve decent penetration.

"I couldn't have a wank as I had a jelly sword"

Sally laughed at Gareth's tiny jelly sword.
by UrbanDef June 7, 2006
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