State requires means for constructing major road (10)
I believe the answer is:
expressway
'road' is the definition.
(I know that expressway is a type of road)
'state requires means' is the wordplay.
'state' becomes 'express' (synonyms).
'requires' means one lot of letters go next to another.
'means' becomes 'way' (a way or means of doing something).
'express'+'way'='EXPRESSWAY'
'for constructing major' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for expressway that I've seen before include "It's driven on by Americans" , "means to get round America" , "Road" , "US name for motorway" , "Urban motorway (US)" .)