house arrest vs confinement

house arrest and confinement both are nouns.

Word	Noun	Adjective	Verb	Adverb
house arrest	Yes	No	No	No
confinement	Yes	No	No	No

As nouns, confinement is a hypernym of house arrest; that is, confinement is a word with a broader meaning than house arrest:

house arrest (noun)	confinement (noun)
confinement to your own home	the act of restraining of a person's liberty by confining them
	the act of keeping something within specified bounds (by force if necessary)
	the state of being confined
	concluding state of pregnancy; from the onset of contractions to the birth of a child