Slub

from WordNet (r) 3.0 (2006)

slub
    n 1: soft lump or unevenness in a yarn; either an imperfection
         or created by design [syn: {slub}, {knot}, {burl}]

from 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]

from 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]

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