Hit second three-wheeler (6)
I believe the answer is:
strike
'hit' is the definition.
('strike' can be a synonym of 'hit')
'second three-wheeler' is the wordplay.
'second' becomes 's' (common abbreviation).
'three-wheeler' becomes 'trike' (I've seen this before).
's'+'trike'='STRIKE'
(Other definitions for strike that I've seen before include "success for bowler" , "Sudden success" , "Hit at a trade dispute" , "Hit or take industrial action" , "Hit forcibly" .)