Refers to a person who practices martial arts, often with a connotation of actual combat or fighting rather than purely spiritual or meditative aspects.
He is a famous martial artist and has won many tournaments.
Training as a martial artist is rigorous.
格闘家 refers specifically to a combat sports athlete or professional fighter, often in modern contexts like MMA or boxing, whereas 武闘家 has a broader, sometimes more traditional or literary feel.
Compound of 武闘 (butō, 'armed fighting; combat') + 家 (ka, 'person; specialist'). The term likely emerged in modern Japanese to describe practitioners of martial arts with an emphasis on fighting.