Conversion (10)
I believe the answer is:
transition
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">conversion</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that conversion can be written as transition)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for transition that I've seen before include "Bridge" , "Change of state, style, etc" , "Conversion" , "sort of element" , "A change from one state to another" .)