Yester

from The Collaborative International Dictionary of English v.0.48

Yester \Yes"ter\, a. [See {Yesterday}.]
   Last; last past; next before; of or pertaining to yesterday.
   [1913 Webster]

         [An enemy] whom yester sun beheld
         Mustering her charms.                    --Dryden.
   [1913 Webster]

   Note: This word is now seldom used except in a few compounds;
         as, yesterday, yesternight, etc.
         [1913 Webster]