A lot of time
I believe the answer is:
ages
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">a lot of time</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 ages that I've seen before include "Rock of - - (hymn)" , "Gets older" , "Epochs" , "Historical eras" , "Aeons" .)