poorhouse vs workhouse

poorhouse and workhouse both are nouns.

Word	Noun	Adjective	Verb	Adverb
poorhouse	Yes	No	No	No
workhouse	Yes	No	No	No

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

poorhouse: an establishment maintained at public expense in order to provide housing for the poor and homeless
workhouse: a poorhouse where able-bodied poor are compelled to labor

poorhouse (noun)	workhouse (noun)
an establishment maintained at public expense in order to provide housing for the poor and homeless	a county jail that holds prisoners for periods up to 18 months
	a poorhouse where able-bodied poor are compelled to labor