line of march vs route

line of march and route both are nouns.

Word	Noun	Adjective	Verb	Adverb
line of march	Yes	No	No	No
route	Yes	No	Yes	No

As nouns, route is a hypernym of line of march; that is, route is a word with a broader meaning than line of march:

Other hypernyms of line of march include itinerary, path.

line of march (noun)	route (noun)
the arrangement of people in a line for marching	an open way (generally public) for travel or transportation
the route along which a column advances	an established line of travel or access

line of march (verb)	route (verb)
	send via a specific route
	divert in a specified direction
	send documents or materials to appropriate destinations