captivity vs internment

captivity and internment both are nouns.

Word	Noun	Adjective	Verb	Adverb
captivity	Yes	No	No	No
internment	Yes	No	No	No

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

Other hyponyms of captivity include durance, life imprisonment.

captivity (noun)	internment (noun)
the state of being a slave	the act of confining someone in a prison (or as if in a prison)
the state of being imprisoned	placing private property in the custody of an officer of the law
	confinement during wartime