thimbleweed vs windflower

thimbleweed and windflower both are nouns.

Word	Noun	Adjective	Verb	Adverb
thimbleweed	Yes	No	No	No
windflower	Yes	No	No	No

As nouns, windflower is a hypernym of thimbleweed; that is, windflower is a word with a broader meaning than thimbleweed:

thimbleweed: a common North American anemone with cylindrical fruit clusters resembling thimbles
windflower: any woodland plant of the genus Anemone grown for its beautiful flowers and whorls of dissected leaves

Other hypernyms of thimbleweed include anemone.

thimbleweed (noun)	windflower (noun)
a common North American anemone with cylindrical fruit clusters resembling thimbles	any woodland plant of the genus Anemone grown for its beautiful flowers and whorls of dissected leaves