As nouns the difference between causeway and superhighway
is that causeway is a road that is raised, as to be above water, marshland etc while superhighway is (us) an expressway, especially one designed for high speeds.
causeway
Noun
(
en noun)
A road that is raised, as to be above water, marshland etc.
Derived terms
* causewayed
* causewaying
superhighway
English
Noun
(
en noun)
(US) An expressway, especially one designed for high speeds.
Derived terms
* information superhighway