swing·er /ˈswɪŋə $ -ər/ noun [countableC] old-fashioned informal 1. someone who is fashionable and goes to a lot of parties 活跃而时髦的人,常参加社交聚会的人
2. someone who has sexual relationships with many people, especially someone who exchanges sexual partners with other people 滥交的人,放荡的人,性开放的人