nonmarried vs unattached

nonmarried

adj
  • Not married. 

noun
  • A person who is not married. 

unattached

adj
  • Not married and not involved in a romantic relationship. 

  • Not connected with or belonging to a particular group or organization. 

  • Not attached or joined; disconnected. 

How often have the words nonmarried and unattached occurred in a corpus of books? (source: Google Ngram Viewer )