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erst

American  
[urst] / ɜrst /

adverb

Archaic.
  1. before the present time; formerly.


erst British  
/ ɜːst /

adverb

  1. long ago; formerly

  2. at first

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of erst

before 1000; Middle English erest, Old English ǣrest (cognate with Old High German ērist, German erst ), equivalent to ǣr ere + -est -est 1