tamoxifen vs antagonist

tamoxifen and antagonist both are nouns.

Word	Noun	Adjective	Verb	Adverb
tamoxifen	Yes	No	No	No
antagonist	Yes	No	No	No

As nouns, antagonist is a hypernym of tamoxifen; that is, antagonist is a word with a broader meaning than tamoxifen:

tamoxifen: an antagonist for estrogen that is used in the treatment of breast cancer
antagonist: a drug that neutralizes or counteracts the effects of another drug

tamoxifen (noun)	antagonist (noun)
an antagonist for estrogen that is used in the treatment of breast cancer	a drug that neutralizes or counteracts the effects of another drug
	a muscle that relaxes while another contracts
	someone who offers opposition