A fighting manuever used when your opponent is too close to punch. A face rub includes anyone of the following: eye goudging, putting one's fingers up another's nose, twisting another's nose, pushing down hard on your opponent's face, grabbing their face and mangling it, any improvised pain inflicted by mashing one's face by grabbing and mashing.
Lorenzo and Sean fought until they fell in between the the trampoline springs, then they just gave each other face rubs until we broke it up.
Noun: The act that results when two people rub their faces together as a sign of affection.
I haven't seen you in ages! Come here and give us a good face rub!