Saint Lawrence Seaway vs ship route

Saint Lawrence Seaway and ship route both are nouns.

Word	Noun	Adjective	Verb	Adverb
Saint Lawrence Seaway	Yes	No	No	No
ship route	Yes	No	No	No

Saint Lawrence Seaway (noun)	ship route (noun)
a seaway involving the Saint Lawrence River and the Great Lakes that was developed jointly by Canada and the United States; oceangoing ships can travel as far west as Lake Superior	a lane at sea that is a regularly used route for vessels