Etymology Dictionary

AFFIANCE,  trust, marriage-contract.  (F.,—L.)   [The verb affy is perhaps obsolete.   It means (1) to trust, confide, Titus Andron. i. 47; and (2) to betroth; Tam. of Shrew, iv. 4. 49.]   Both affye and affiance occur in Rob. of Brunne's tr. of P. Langtoft, pp. 87, 155.   1. The verb is from O.F. affier, to trust in, also spelt afier; which is from a- (Lat. ad ), and fier, formed from Low Lat. fidare, a late form from Lat. fidere, to trust.   2. The sb. is from O.F. afiance, which is compounded of a- (Lat. ad ) and fiance, formed from Low Lat. fidantia, a pledge, security; which is from the same Low Lat. fidare, pres. pt. fidans, of which the stem is fidant-.   Thus both are reduced to Lat. fidere, to trust. + Gk. πείθειν, to persuade, whence πέποιθα, I trust.—✔BHIDH, perhaps meaning to pledge or oblige; a weakened form of ✔BHANDH, to bind.   See Bind.   So Curtius, i. 325.   β. Fick also gives ✔BHIDH, but assigns to it the idea of 'await, expect, trust,' and seems to connect it with E. bide.   See Bide.   Der. affiance, verb; affianc-ed.