Desert streambed
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">desert streambed</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for wadi that I've seen before include "seasonal flower" , "Seasonal water channel" , "River valley; dry bed" , "Periodic water channel" , "Dry North African river bed" .)