lithophyte vs rock plant

lithophyte and rock plant both are nouns.

Word	Noun	Adjective	Verb	Adverb
lithophyte	Yes	No	No	No
rock plant	Yes	No	No	No

As nouns, rock plant is a hypernym of lithophyte; that is, rock plant is a word with a broader meaning than lithophyte:

lithophyte: plant that grows on rocks or stony soil and derives nourishment from the atmosphere
rock plant: plant that grows on or among rocks or is suitable for a rock garden

lithophyte (noun)	rock plant (noun)
plant that grows on rocks or stony soil and derives nourishment from the atmosphere	plant that grows on or among rocks or is suitable for a rock garden