polyanthus vs primrose

polyanthus and primrose both are nouns.

Word	Noun	Adjective	Verb	Adverb
polyanthus	Yes	No	No	No
primrose	Yes	No	No	No

As nouns, primrose is a hypernym of polyanthus; that is, primrose is a word with a broader meaning than polyanthus:

polyanthus: florists' primroses; considered a complex hybrid derived from oxlip, cowslip, and common primrose
primrose: any of numerous short-stemmed plants of the genus Primula having tufted basal leaves and showy flowers clustered in umbels or heads

Other hypernyms of polyanthus include primula.

polyanthus (noun)	primrose (noun)
florists' primroses; considered a complex hybrid derived from oxlip, cowslip, and common primrose	any of numerous short-stemmed plants of the genus Primula having tufted basal leaves and showy flowers clustered in umbels or heads