The term itself means "Fire in the Hole!.
A popular term used in SOCOM. The Asian terrorists would scream out "QUALIBHAD" as they hurled a grenade at an enemy.
Also can be used to taunt people in low paying, humiliating jobs. EX: Toll Booth guy, Gas station attendant, and sometimes customers of a supermarket.
(Typical example of Qualibhad use:)
Yo, did you hear me scream out Qualibhad to the lady at the toll booth?
Yeah dude, you showed her!