widow woman vs dowager

widow woman and dowager both are nouns.

Word	Noun	Adjective	Verb	Adverb
widow woman	Yes	No	No	No
dowager	Yes	No	No	No

As nouns, dowager is a hyponym of widow woman; that is, dowager is a word with a more specific, narrower meaning than widow woman:

widow woman: a woman whose husband is dead especially one who has not remarried
dowager: a widow holding property received from her deceased husband

Other hyponyms of widow woman include war widow.

widow woman (noun)	dowager (noun)
a woman whose husband is dead especially one who has not remarried	a widow holding property received from her deceased husband