The term 'BOUT ENDERS, BRIEFLY' can be solved by the crossword solutions PINS (4 letters), KAYOS (5 letters), REF (3 letters), and KOS (3 letters). PINS is an abbreviation for 'pinned, ' which is a wrestling term meaning to hold an opponent's shoulders on the mat for a certain amount of time. KAYOS is an abbreviation for 'KNOCKOUT, ' which is a boxing term meaning to render an opponent unconscious. REF is an abbreviation for 'REFEREE, ' which is a person who enforces the rules of a sport and makes sure the bout is fair. KOS is an abbreviation for 'KNOCKOUT streak, ' which is a boxing term meaning a series of consecutive wins by KNOCKOUT.