Communion (4)
I believe the answer is:
mass
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">communion</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that communion can be written as Mass)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for mass that I've seen before include "Catholic church service" , "Body of matter" , "state, in short" , "Bulk - RC service" , "Roman Catholic service" .)