[1] : 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
see also:
yesterday 

Yester >> Y Words
Yester, definition of term: Yester
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