light o' love

Noun

light-o'-love (plural lights-o'-love)

1. An old dance tune, whose name made it a proverbial expression of levity, especially in love matters.
   • Best sing it to the tune of light o' love.c. 1590–1591 (date written), William Shakespeare, “The Two Gentlemen of Verona”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and...
2. Someone who is inconstant in love; a flirt.
   • You light-o'-love, a word or two.1626 February 13 (licensing date; Gregorian calendar), Francis Beaumont, John Fletcher, “The Noble Gentleman”, in Comedies and Tragedies […], London: […] Humphrey Robinson, […], and for Humphrey...
3. A promiscuous woman; a prostitute; a mistress or female lover.
   • Thus they fared, one after another, as the light-o'-love dame introduced them into her chamber, so that no one ventured to come near her.1828, Thomas Keightley, The Fairy Mythology, volume II, London: William Harrison Ainsworth