Religious sister (3)
I believe the answer is:
nun
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">religious sister</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for nun that I've seen before include "She's a member of a religious community" , "She's made vows" , "Member of convent" , "Domestic fancy pigeon" , "Devout woman" .)