periphery vs boundary

periphery and boundary both are nouns.

Word	Noun	Adjective	Verb	Adverb
periphery	Yes	No	No	No
boundary	Yes	No	No	No

As nouns, boundary is a hypernym of periphery; that is, boundary is a word with a broader meaning than periphery:

Other hypernyms of periphery include bound, edge.

periphery (noun)	boundary (noun)
the outside boundary or surface of something	the greatest possible degree of something
	the line or plane indicating the limit or extent of something
	a line determining the limits of an area