bract vs calyculus

bract and calyculus both are nouns.

Word	Noun	Adjective	Verb	Adverb
bract	Yes	No	No	No
calyculus	Yes	No	No	No

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

bract: a modified leaf or leaflike part just below and protecting an inflorescence
calyculus: a group of bracts simulating a calyx as in a carnation or hibiscus

Other hyponyms of bract include calycle, epicalyx, false calyx, bracteole, bractlet, spathe, involucre, glume.

bract (noun)	calyculus (noun)
a modified leaf or leaflike part just below and protecting an inflorescence	a small cup-shaped structure (as a taste bud or optic cup or cavity of a coral containing a polyp)
	a group of bracts simulating a calyx as in a carnation or hibiscus