dalliance vs double date

dalliance

noun
  • Playful flirtation; amorous play. 

  • A sexual relationship, not serious but often illicit. 

  • A wasting of time in idleness or trifles. 

  • A episode of dabbling. 

double date

noun
  • A (romantic) date that two couples go on together. 

verb
  • To go on a double date. 

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