sea lane vs trade route

sea lane and trade route both are nouns.

Word	Noun	Adjective	Verb	Adverb
sea lane	Yes	No	No	No
trade route	Yes	No	No	No

As nouns, sea lane and trade route are synonyms defined as:

sea lane and trade route: a lane at sea that is a regularly used route for vessels

Other synonyms of sea lane include seaway, ship route.

sea lane (noun)	trade route (noun)
a lane at sea that is a regularly used route for vessels	a lane at sea that is a regularly used route for vessels
	a route followed by traders (usually in caravans)