Brawling (GURPS) is one of Fallout GURPS skills. See: Fallout GURPS.
The skill of unscientific, unarmed combat. When you punch or kick, roll vs. Brawling to hit, and add !/10 of your skill (round down) to damage. You may parry bare-handed attacks at @/3 skill.”— Steve Jackson Games GURPS sources
With the abandonment of GURPS, Brawling (GURPS) was merged into Unarmed.