Source : Webster's Revised Unabridged Dictionary (1913)

Visa \Vi"sa\, n. [F.]
   See {Vis?}.

Visa \Vi"sa\, v. t. [imp. & p. p. {Visaed}; p. pr. & vb. n.
   {Visaing}.]
   To indorse, after examination, with the word vis['e], as a
   passport; to vis['e].

Source : WordNet®

visa
     n : an endorsement made in a passport that allows the bearer to
         enter the country issuing it
     v 1: provide (a passport) with a visa
     2: approve officially; "The list of speakers must be visaed"