three-mile limit vs limit

three-mile limit and limit both are nouns.

Word	Noun	Adjective	Verb	Adverb
three-mile limit	Yes	No	No	No
limit	Yes	No	Yes	No

As nouns, limit is a hypernym of three-mile limit; that is, limit is a word with a broader meaning than three-mile limit:

Other hypernyms of three-mile limit include demarcation, demarcation line.

three-mile limit (noun)	limit (noun)
the limit of a nation's territorial waters	the greatest possible degree of something
	the boundary of a specific area
	as far as something can go
	the greatest amount of something that is possible or allowed
	the mathematical value toward which a function goes as the independent variable approaches infinity
	final or latest limiting point

three-mile limit (verb)	limit (verb)
	restrict or confine within limits
	place limits on (extent or amount or access)
	decide upon or fix definitely