Lumpy, gnarled (6)
I believe the answer is:
knotty
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">lumpy</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >'<span class="explanation-format__original">gnarled</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that gnarled can be written as knotty)</span><br/ ><br/ ></span>
(Other definitions for knotty that I've seen before include "Full of tangles; extremely intricate" , "Difficult (point)" , "Very difficult - complex" , "Difficult - having hard lumps (of wood)" , "puzzling" .)