light-o'-love vs light-of-love

light-o'-love

noun
  • A flirtatious or wanton woman. 

  • An old tune of a dance, the name of which made it a proverbial expression of levity, especially in love matters. 

light-of-love

How often have the words light-o'-love and light-of-love occurred in a corpus of books? (source: Google Ngram Viewer )