Supported by (4)
I believe the answer is:
upon
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">supported by</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for upon that I've seen before include "On tope of" , "voucher, business stopped" , "Onto" , "Straddling" , "Thereafter" .)