Stick nothing in the middle of the road! (3)
I believe the answer is:
rod
'stick' is the definition.
(I've seen this before)
'nothing in the middle of the road' is the wordplay.
'nothing' becomes 'O' (O resembles 0).
'in the middle of' is an insertion indicator.
'the road' becomes 'rd' (abbreviation).
'o' going inside 'rd' is 'ROD'.
(Other definitions for rod that I've seen before include "An angler's stick" , "Staff" , "Rigid stick" , "axle" , "Fisherman's item" .)