Definition of green gown in US English:

green gown

noun

historical, archaic
  • A dress stained green from rolling in grass. Chiefly in "to give a woman a green gown": to engage in amorous play with a woman; (euphemism) to deflower, deprive a woman of her virginity.

Origin

Late 16th century; earliest use found in Philip Sidney (1554–1586), author and courtier. From green + gown.

Pronunciation

green gown

/ˌɡriːn ˈɡaʊn/