The Collaborative International Dictionary of English v.0.48:

Knotty \Knot"ty\, a. [Compar. Knottier; superl. Knottiest.]
   1. Full of knots; knotted; having many knots; as, knotty
      timber; a knotty rope.
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   2. Hard; rugged; as, a knotty head. [R.] --Rewe.
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   3. Difficult; intricate; perplexed.
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            A knotty point to which we now proceed --Pope.
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