Mischievous trick (5)
I believe the answer is:
prank
'mischievous trick' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for prank that I've seen before include "(Amusing) trick" , "Mischievous trick" , "April fool" , "High-spirited mischief" , "Practical joke or trick" .)