common tarweed vs wildflower

common tarweed and wildflower both are nouns.

Word	Noun	Adjective	Verb	Adverb
common tarweed	Yes	No	No	No
wildflower	Yes	No	No	No

As nouns, wildflower is a hypernym of common tarweed; that is, wildflower is a word with a broader meaning than common tarweed:

common tarweed: California annual having red-brown spots near the base of its yellow flower rays
wildflower: wild or uncultivated flowering plant

Other hypernyms of common tarweed include wild flower.

common tarweed (noun)	wildflower (noun)
California annual having red-brown spots near the base of its yellow flower rays	wild or uncultivated flowering plant