billet-doux

[bil-ey-doo, bil-ee-, bee-yey-doo]

noun

plural

billets-doux 

1. a love letter.

billet-doux

/ bijɛdu, ˌbɪlɪˈduː /

noun

1. old-fashioned,  a love letter

Word History and Origins

Origin of billet-doux¹

1665–75; < French: literally, sweet note. See billet ¹, douce

Word History and Origins

Origin of billet-doux¹

C17: from French, literally: a sweet letter, from billet (see _billet ¹ ) + doux sweet, from Latin dulcis