DICT.TW Dictionary Taiwan

 erst /ˈɝst/
 (ad.)以前,往昔的

 Erst adv.  [Archaic]
 1. First.
 2. Previously; before; formerly; heretofore.
    Tityrus, with whose style he had erst disclaimed all ambition to match his pastoral pipe.   --A. W. Ward.
 At erst, at first; at the beginning.
 Now at erst, at this present time.
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 erst
      adv : at a previous time; "once he loved her"; "her erstwhile
            writing" [syn: once, formerly, at one time, erstwhile]