[1] : The Collaborative International Dictionary of English v.0.48

erst \erst\ ~erst, adv. orig. superlative of ere; as.
   =aerest. see ere. archaic
   1. first. --chaucer.
      1913 webster

   2. previously; before; formerly; heretofore. --chaucer.
      1913 webster

            tityrus, with whose style he had erst disclaimed all
            ambition to match his pastoral pipe.  --a. w. ward.
      1913 webster

   at erst, at first; at the beginning.

   now at erst, at this present time. --chaucer.
      1913 webster
see also:
ere at erst now at erst 

[2] : WordNet (r) 2.0

erst
     adv : at a previous time; "once he loved her"; "her erstwhile
           writing" syn: once, formerly, at one time, erstwhile
see also:
once formerly at one time erstwhile 

Erst >> E Words
Erst, definition of term: Erst
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