Module
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">module</span>' is the definition.<br/ ><span class="explanation-format__explanation">(both can mean a part of something)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for unit that I've seen before include "Self-contained part" , "Single piece - kitchen cabinet" , "Army division" , "Individual component" , "1 entity" .)