Annual celebration (3,4)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">annual celebration</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that New Year is a holiday)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for new year that I've seen before include "different diary now?" , "January 1st" , "Early days?" , "Resolve now" , "This is only five days old" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">annual celebration</span>' is the definition.<br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for birthday that I've seen before include "Invisible threads?" , "Personal anniversary of origin" , "Anniversary celebration" , "Hardy bit (anag)" , "Natal day" .)
(Another definition for christmas party that I've seen is " annual event - with 29ac".)