epilith vs organism

epilith and organism both are nouns.

Word	Noun	Adjective	Verb	Adverb
epilith	Yes	No	No	No
organism	Yes	No	No	No

As nouns, organism is a hypernym of epilith; that is, organism is a word with a broader meaning than epilith:

epilith: A plant, fungus, or other organism that grows upon rock.
organism: a living thing that has (or can develop) the ability to act or function independently

Other hypernyms of epilith include being.

epilith (noun)	organism (noun)
A plant, fungus, or other organism that grows upon rock.	a living thing that has (or can develop) the ability to act or function independently
	a system considered analogous in structure or function to a living body