antagonist vs tamoxifen

antagonist and tamoxifen both are nouns.

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

As nouns, tamoxifen is a hyponym of antagonist; that is, tamoxifen is a word with a more specific, narrower meaning than antagonist:

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

Other hyponyms of antagonist include estrogen antagonist, narcotic antagonist.

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