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billet-doux

[bil-ey-doo, bil-ee-; French bee-yey-doo]
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noun, plural bil·lets-doux [bil-ey-dooz, bil-ee-; French bee-yey-doo] /ˈbɪl eɪˈduz, ˈbɪl i-; French bi yeɪˈdu/.

a love letter.

Origin of billet-doux

1665–75; < French: literally, sweet note. See billet1, douce
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for billet-doux

Historical Examples of billet-doux

  • He summoned me into his study, where I saw my billet-doux lying on the table.

    Tom, Dick and Harry

    Talbot Baines Reed

  • A papal excommunication is a billet-doux compared to the Commination of Jugana.

  • Excuse me, Mr. Coates, I must have a peep at her ladyship's billet-doux.

    Rookwood

    William Harrison Ainsworth

  • They receive a challenge like a "billet-doux," and a home-thrust as a favour.

    Thackerayana

    William Makepeace Thackeray

  • Twenty to seven,—seven oclock they were due at the Billet-doux.

    Twos and Threes

    G. B. Stern

British Dictionary definitions for billet-doux

billet-doux

noun plural billets-doux (ˌbɪlɪˈduːz, French bijɛdu)

old-fashioned, or jocular a love letter

Word Origin for billet-doux

C17: from French, literally: a sweet letter, from billet (see billet 1) + doux sweet, from Latin dulcis
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
Word Origin and History for billet-doux
n.

also billet doux, 1670s, "love letter," French, literally "sweet note," from billet "document, note" (14c., diminutive of bille; see bill (n.1)) + doux "sweet," from Latin dulcis (see dulcet).

Online Etymology Dictionary, © 2010 Douglas Harper