billet-doux

plural billets-doux · alternative billet doux

1. A love letter.

   Adonis calls for a 'pick-me-up' before he has strength enough to answer a billet-doux from Venus.

   1873, [Edward Bulwer-Lytton], chapter VI, in Kenelm Chillingly: His Adventures and Opinions […], volume II, Edinburgh; London: William Blackwood and Sons, →OCLC, book IV, page 253

   2 more examples

   "O heavenly, heavenly flowers!" exclaimed Miss Sharp, and smelt them delicately, and held them to her bosom, and cast up her eyes to the ceiling, in an ecstasy of admiration. Perhaps she just looked first into the bouquet, to see whether there was a billet-doux hidden among the flowers; but there was no letter.

   1847 January – 1848 July, William Makepeace Thackeray, chapter IV, in Vanity Fair […], London: Bradbury and Evans […], published 1848, →OCLC, page 31

   When he offered her his hand, she would refuse it—not because she “knew her place,” but because she did not love him. [...] Her corded trunk, heavier by another packet of billets-doux and a month’s salary in advance, was soon carried up the stairs of some other house.

   1911, Max Beerbohm, chapter II, in Zuleika Dobson