Every two weeks (11)
I believe the answer is:
fortnightly
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">every two weeks</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for fortnightly that I've seen before include "Every two weeks" , "Every fourteen days" , "at regular intervals" .)