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Synonyms

billet-doux

American  
[bil-ey-doo, bil-ee-, bee-yey-doo] / ˈbɪl eɪˈdu, ˈbɪl i-, bi yeɪˈdu /

noun

plural

billets-doux

  1. a love letter.

billet-doux British  
/ bijɛdu, ˌbɪlɪˈduː /

noun

  1. old-fashioned a love letter

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of billet-doux

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

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.