one-night stand vs sexual relations

one-night stand

noun
  • Either of the two partners involved in such a single sexual encounter. 

  • A single sexual encounter between two individuals, where at least one of the partners has no immediate intention or expectation of establishing a longer-term sexual or romantic relationship. As the phrase implies, the relationship lasts for only one night. 

  • An occasion when a performer or team of them (especially in vaudeville) expects to perform at a theater for a single evening. 

sexual relations

noun
  • Sexual activities between individuals. 

  • The act of sexual intercourse. 

How often have the words one-night stand and sexual relations occurred in a corpus of books? (source: Google Ngram Viewer )