Thenceforth
I believe the answer is:
thereafter
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">thenceforth</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for thereafter that I've seen before include "Next" , "later" , "Following that time" , "Subsequently" .)