Hyper
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">hyper</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 ultra that I've seen before include "Extreme (as in UV)" , "Far beyond the norm" , "Prefix meaning beyond or extremely" , "Immoderate" , "such sound treatment?" .)