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

darn \darn\ daumrn, v. t. imp.  p. p. darned
   daumrnd; p. pr.  vb. n. darning. oe. derne, prob. of
   celtic origin; cf. w. darnio to piece, break in pieces, w. 
   arm. to e. tear. cf. tear, v. t.
   to mend as a rent or hole, with interlacing stitches of yarn
   or thread by means of a needle; to sew together with yarn or
   thread.
   1913 webster

         he spent every day ten hours in his closet, in darning
         his stockings.                           --swift.
   1913 webster

   darning last. see under last.

   darning needle.
   a a long, strong needle for mending holes or rents,
       especially in stockings.
   b zool. any species of dragon fly, having a long,
       cylindrical body, resembling a needle. these flies are
       harmless and without stings.

   note: in this sense, usually written with a hyphen. called
         also devil's darning-needle.
         1913 webster
see also:
darned darning tear darning last last darning needle 
devil's darning-needle 

[2] : WordNet (r) 2.0

darning
     n : the act of mending a hole in a garment with crossing threads

Darning >> D Words
Darning, definition of term: Darning
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