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

warn \warn\ waddrn, v. t. oe. wernen, as. weornan, wyrnan.
   cf. warn to admonish.
   to refuse. written also wern, worn. obs. --chaucer.
   1913 webster
see also:
warn wern worn 

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

wern \wern\, v. t. see 1st warn.
   to refuse. obs.
   1913 webster

         he is too great a niggard that will wern
         a man to light a candle at his lantern.  --chaucer.
   1913 webster
see also:
warn 

Wern >> W Words
Wern, definition of term: Wern
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