Spiny succulent (6)
I believe the answer is:
cactus
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">spiny succulent</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for cactus that I've seen before include "Drought-resistant plant" , "Eg, prickly pear" , "Desert flower" , "Thorny desert plant" , "plant, succulent one" .)