boundary vs margin

boundary and margin both are nouns.

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

As nouns, margin is a hyponym of boundary; that is, margin is a word with a more specific, narrower meaning than boundary:

boundary (noun)	margin (noun)
the greatest possible degree of something	an amount beyond the minimum necessary
the line or plane indicating the limit or extent of something	a permissible difference; allowing some freedom to move within limits
a line determining the limits of an area	the blank space that surrounds the text on a page
	the amount of collateral a customer deposits with a broker when borrowing from the broker to buy securities
	(finance) the net sales minus the cost of goods and services sold
	the boundary line or the area immediately inside the boundary