a fight, argument, contest, etc., open to everyone and usually without rules.

any competition or contested situation that is disordered, impulsive, or out of control

a free-for-all at the buffet table.

Informal . any enterprise or field of endeavor in which various companies, countries, participants, etc., compete without restriction

a price-cutting free-for-all among local stores.

open to everyone.

noun

calm , harmony , peace

noun

affray , battle , brawl , broil * , brouhaha * , fracas , fray , knock-down-drag-out , melee , riot , row , ruction , broil , donnybrook , tumult , brouhaha , fight , ruckus , scrap , set-to