plant toxin vs brucine

plant toxin and brucine both are nouns.

Word	Noun	Adjective	Verb	Adverb
plant toxin	Yes	No	No	No
brucine	Yes	No	No	No

As nouns, brucine is a hyponym of plant toxin; that is, brucine is a word with a more specific, narrower meaning than plant toxin:

plant toxin: any substance produced by plants that is similar in its properties to extracellular bacterial toxin
brucine: a bitter alkaloid poison resembling strychnine and extracted from nux vomica

Other hyponyms of plant toxin include nicotine, strychnine, hemlock, mycotoxin, curare, tubocurarine.

plant toxin (noun)	brucine (noun)
any substance produced by plants that is similar in its properties to extracellular bacterial toxin	a bitter alkaloid poison resembling strychnine and extracted from nux vomica