1. (noun) Slang term for a penis usually used in the context of sexuality.

2. (noun) A pointed instrument thrown for distance in competitive sports similar to a javelin but is made of a viscous material and rarely sticks in the ground on impact. Much less popular than a wood harpoon or a steel harpoon. Can also be used in hunting but is rarely effective as it usually bounces off the animal being hunted.
1.

SMITTY: So? Would you throw Ugly Betty the ol' goo harpoon or what?
WAYNE: Naw, man. Not unless I had about ten beers in me.

2.

The Swedish athlete was disqualified because he tripped over his own goo harpoon.
by Mickey Nation February 8, 2007
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