1. After killing an opponent in any of the Halo games, the act of standing on the dead players head, and bobbing up an down, in other words, to hump the head of your dead enemy.
2. Team humping is fun also, when members of a team get together to desecrate the body of their slain enemy.
3. In halo 3 your opponents online cannot hear you talk/gloat so "head humping" will be all the more common way of saying a polite.. "I FUCKED YOU".
4. The way in which you let the enemy know who's boss.
5. Putting noobs and bitches in their place.
J : Did you see me own that noob?
C : Yeah, and then you humped him too
JLO: It's time for a team hump next time
After no scoping a rocket wielding enemy J head humped the shit out of him.
When a person, usually a boy, stands infront of the victim, with the victims head at penis height, grabbing the back of the head and pumping twice, thrusting the penis into the face of the victim, whilst saying "UNSA UNSA".
This usually causes great embarassment, and ones face is left feeling rather defiled.
Dan: Damn, I just got head humped!
Paul: Oh *Precedes to head hump dan* UNSA UNSA
Dan: F*%KING HELL