sexual union
性结合
例句与用法：
A romantic and sexual relationship, sometimes one of brief duration, between two people who are not married to each other.
风流韵事，绯闻两个没有婚姻关系的人之间浪漫的和性的关系，有时是短暂的
A woman who has a continuing sexual relationship with a usually married man who is not her husband and from whom she generally receives material support.
情妇与通常是已婚但又不是自己丈夫的男子保持长久的性关系，并从他那里得到物质支持的女人
Relating to or characteristic of an inactive or submissive role in a relationship, especially a sexual relationship.
消极的，被动的关于在一种关系中不活跃的、被动的或具有此种特征的，尤指性关系
A man who has a continuing sexual relationship with and receives financial support from a woman.
靠女人赡养的男人，吃软饭的男人，小白脸与一妇女有持续的性关系并从她那儿得到财力支持的男人