柯林斯词典sphincter /ˈsfɪŋktə/ (sphincters) 1. N-COUNT A sphincter is a ring of muscle that surrounds an opening to the body and that can tighten to close this opening. 括约肌[技术] ...the anal sphincter. ...肛门括约肌。 返回 sphincter剑桥词典a muscle that surrounds an opening in the body and can tighten to close it 括约肌 the anal sphincter 肛门括约肌 a sphincter muscle 括约肌 返回 sphincter