Late start - stay and loiter with intent (3,2,4)
I believe the answer is:
lie in wait
'late start' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.
'stay and loiter with intent' is the wordplay.
'stay' becomes 'wait' (I've seen this before).
'and' means one lot of letters go next to another.
'loiter with intent' becomes 'liein' (I am not sure about this - if you are sure you should believe this answer much more).
'wait' after 'liein' is 'LIE IN WAIT'.
Can you help me to learn more?
(Other definitions for lie in wait that I've seen before include "hover" , "Plan for ambush" , "Plan to attack" , "as some bushwhackers do" , "Be ready to surprise" .)