Every other (9)
I believe the answer is:
alternate
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">every other</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for alternate that I've seen before include "Change from one thing to another by turns" , "Happening or following in turns, one after the other" , "Act reciprocally" , "Happen in turns, rotate" , "Occur in turn repeatedly" .)