What does the word knotty mean?

Usage examples for knotty

  1. The sides of their body project in a remarkable degree; their skin is enormously thick, knotty in its surface, and has but a few hairs scattered over it. – Anecdotes of the Habits and Instinct of Animals by R. Lee
  2. It must be a very knotty one. – Harley Greenoak's Charge by Bertram Mitford
  3. It is curious to observe that in this trial the by- standers were several times appealed to for an expression of opinion on some knotty question. – Nooks and Corners of the New England Coast by Samuel Adams Drake