Newlyweds' holiday (9)
I believe the answer is:
honeymoon
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">newlyweds' holiday</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 honeymoon that I've seen before include "Post-reception break" , "Sequel to marriage" , "Holiday of a newly married couple" , "Post-nuptial holiday" , "Holiday just for two?" .)