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

slub \slub\, n. etymol. uncertain.
   a roll of wool slightly twisted; a rove; -- called also
   slubbing.
   1913 webster
see also:
slubbing 

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

slub \slub\, v. t. imp.  p. p. slubbed; p. pr.  vb. n.
   slubbing.
   to draw out and twist slightly; -- said of slivers of wool.
   1913 webster
see also:
slubbed slubbing 

[3] : WordNet (r) 2.0

slub
     n : soft lump or unevenness in a yarn; either an imperfection or
         created by design syn: knot, burl
see also:
knot burl 

Slub >> S Words
Slub, definition of term: Slub
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