Midmonth date (4)
I believe the answer is:
ides
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">midmonth date</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for ides that I've seen before include "Julius Caesar was told to beware the . . . . of March" , "March 15; dies (anag.)" , "(In March) Caesar's time to beware" , "Caesar's fateful day" , "Caesar's bad day in March" .)