To jam your thumb up under someones soft underpart of the jaw
I shit on cats and jaw tap em
ayon kay Karama11 ika-10 ng Nobyembre, 2008
1 more definition
To tap someone underneath their jaw showing disrespect.
After I win a fight I kick the kid then I jaw tap'm
ayon kay SuperWombat ika-27 ng Pebrero, 2009