starry saxifrage vs rockfoil

starry saxifrage and rockfoil both are nouns.

Word	Noun	Adjective	Verb	Adverb
starry saxifrage	Yes	No	No	No
rockfoil	Yes	No	No	No

As nouns, rockfoil is a hypernym of starry saxifrage; that is, rockfoil is a word with a broader meaning than starry saxifrage:

starry saxifrage: small often mat-forming alpine plant having small starlike white flowers; Europe
rockfoil: any of various plants of the genus Saxifraga

Other hypernyms of starry saxifrage include breakstone, saxifrage.

starry saxifrage (noun)	rockfoil (noun)
small often mat-forming alpine plant having small starlike white flowers; Europe	any of various plants of the genus Saxifraga