Ash Wednesday starts it (4)
I believe the answer is:
lent
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">ash wednesday starts it</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for lent that I've seen before include "Gave the use of for a time" , "From Ash Wednesday to Holy Saturday" , "Period of penance" , "Pre-Easter period" , "Gave for a limited period" .)