Worker I caught in prank (5)
I believe the answer is:
antic
'prank' is the definition.
('antic' can be a synonym of 'prank')
'worker i caught' is the wordplay.
'worker' becomes 'ant' (worker is a type of ant**).
'caught' becomes 'c' (cricket abbreviation).
'ant'+'i'+'c'='ANTIC'
'in' acts as a link.
(Other definitions for antic that I've seen before include "Ludicrous act done for fun" , "Tomfoolery" , "Caper; grotesque (arch.)" , "Grotesque, fantastic (archaic)" , "Caper, trick" .)