['jestә(r)]
adj.
<古><诗>昨日的
在这以前的

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

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

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