weeds vs widow's weeds

weeds and widow's weeds both are nouns.

Word	Noun	Adjective	Verb	Adverb
weeds	Yes	No	No	No
widow's weeds	Yes	No	No	No

As nouns, weeds and widow's weeds are synonyms defined as:

weeds and widow's weeds: a black garment (dress) worn by a widow as a sign of mourning

weeds (noun)	widow's weeds (noun)
a black garment (dress) worn by a widow as a sign of mourning	a black garment (dress) worn by a widow as a sign of mourning