athletic supporter
noun🔊/æθˌletɪk səˈpɔːtə(r)/
🔊/æθˌletɪk səˈpɔːrtər/
(especially North American English) (also jockstrap British and North American English)
a piece of men’s underwear worn to support or protect the sexual organs while playing sports （男子运动时穿的）下体护身