Realms (7)
I believe the answer is:
domains
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">realms</span>' is the definition.<br/ ><span class="explanation-format__explanation">('domain' can be a synonym of 'realm')</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for domains that I've seen before include "Realms" , "Areas" .)