Source : Webster's Revised Unabridged Dictionary (1913)

Vouchsafe \Vouch*safe"\, v. t. [imp. & p. p. {Vouchsafed}; p.
   pr. & vb. n. {Vouchsafing}.] [Vouch + safe, that is, to vouch
   or answer for safety.]
   1. To condescend to grant; to concede; to bestow.

            If ye vouchsafe that it be so.        --Chaucer.

            Shall I vouchsafe your worship a word or two?
                                                  --Shak.

            It is not said by the apostle that God vouchsafed to
            the heathens the means of salvation.  --South.

   2. To receive or accept in condescension. [Obs.] --Shak.

Vouchsafe \Vouch*safe"\, v. i.
   To condescend; to deign; to yield; to descend or stoop.
   --Chaucer.

         Vouchsafe, O Lord, to keep us this day without sin.
                                                  --Bk. of Com.
                                                  Prayer.

         Vouchsafe, illustrious Ormond, to behold What power the
         charms of beauty had of old.             --Dryden.

Source : WordNet®

vouchsafe
     v 1: grant in a condescending manner
     2: promise or agree condescendingly, as a special favor