The Collaborative International Dictionary
Desponsage
Desponsage \De*spon"sage\, n. [From L. desponsus, p. p. See Despond.] Betrothal. [Obs.]
Ethelbert . . . went peaceably to King Offa for
desponsage of Athilrid, his daughter.
--Foxe.
Wiktionary
desponsage
n. (context obsolete English): Betrothal.