What is Brawl?

Legal Definition
A clamorous or tumultuous quarrel in a public placo, to the disturbance of the public peace. In English law, specifically, a noisy quarrel or other uproarious conduct creating a disturbance in a church or churchyard. 4 BL Comm 146; 4 Steph. Comm. 253. The popular meanings of the words "brawls" and "tumults" are substantially the same and identical. They are correlative terms, the one employed to express the meaning of the other, and are so defined by approved lexicographers. Legally, they mean the same kind of disturbance to the public peace, produced by the same class of agents, and can be well comprehended to define one and the same offence. State v. Perkins, 42 N. H. 464.
-- Black's Law Dictionary
Legal Definition
A noisy quarrel.
-- Ballentine's Law Dictionary