Gallop easily (6)
I believe the answer is:
canter
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">gallop easily</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 canter that I've seen before include "(Horse's) pace between a trot and a gallop" , "Ride at a quick pace" , "Run" , "Moderate pace for horse" , "Gentle movement in bay, say" .)