caryopsis vs amaranth

caryopsis and amaranth both are nouns.

Word	Noun	Adjective	Verb	Adverb
caryopsis	Yes	No	No	No
amaranth	Yes	No	No	No

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

caryopsis: dry seed-like fruit produced by the cereal grasses: e.g. wheat, barley, Indian corn
amaranth: seed of amaranth plants used as a native cereal in Central and South America

Other hyponyms of caryopsis include barleycorn, wheat berry, kernel, rye.

caryopsis (noun)	amaranth (noun)
dry seed-like fruit produced by the cereal grasses: e.g. wheat, barley, Indian corn	any of various plants of the genus Amaranthus having dense plumes of green or red flowers; often cultivated for food
	seed of amaranth plants used as a native cereal in Central and South America