Problematic (6)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">problematic</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for thorny that I've seen before include "Problematic; spiny" , "Difficult; prickly" , "Bristling with perplexities" , "Covered in spikes" , "Trying" .)
(Other definitions for tricky that I've seen before include "Complicated" , "Thorny" , "Crafty, foxy, slippery" , "Crafty or difficult" , "Awkwardly difficult" .)