Read the dictionary definition of boxer. All definitions for this word.
1. a breed of stocky medium-sized short-haired dog with a brindled coat and square-jawed muzzle developed in Germany
2. someone who fights with his fists for sport
3. a member of a nationalistic Chinese secret society that led an unsuccessful rebellion in 1900 against foreign interests in China
4. a workman employed to pack things into containers
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Merriam-Webster definition of boxer