Christian festival (6)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">christian festival</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 easter that I've seen before include "Christian celebration of the Resurrection" , "Snug retreat" , "Annual religious festival" , "Resurrection festival" , "Christian celebration at the end of Lent" .)
(Other definitions for mardi gras that I've seen before include "Time for carnival" , "festive occasion" , "Carnival (day)" , "pre-Lent festival" , "Shrove Tuesday festival" .)