Punishment with nothing getting in the way (3)
I believe the answer is:
rod
'punishment' is the definition.
(stick used for corporal punishment)
'nothing getting in the way' is the wordplay.
'nothing' becomes 'O' (looks like zero - 0).
'getting in' means one lot of letters goes inside another.
'the way' becomes 'rd' (short for road).
'o' going inside 'rd' is 'ROD'.
'with' acts as a link.
(Other definitions for rod that I've seen before include "An angler's stick" , "Wand - fishing stick" , "Baton, pole" , "A few yards" , "that most anglers use" .)