Ungaza is a term used to tell someone that you are going to take down their pants and underwear and start violently beating their dick until it starts to turnpurple.
The word Tarzan used to communicate to the animals; Also used by Dave Chappelle in the racial draft episode as a parody for how white people address other races.
Like the other guy said, it seems to originate in Tarzan movies but it was co-opted by Black teens in Oakland during the 70s (I'm okay about being corrected here - earlier?) as a slang power-grunt.
I'd love to see someone provide additional words to my example. It's been a LONG time...
Foot-stomping chant (by late 70s it was used by cheerleaders and double-dutch):
Ungh, ungawa
Momma's got the powa
I said it, I meant it
I'm here to represent it
My back is achin', My belt's too tight My hips are shakin' from left to right...