Every 60 minutes (6)
I believe the answer is:
hourly
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">every 60 minutes</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 hourly that I've seen before include "Every 60 minutes" , "Every sixty minutes" , "Every 3,600 seconds" .)