clastic vs clastic rock

clastic is not a noun while clastic rock is a noun.

Word	Noun	Adjective	Verb	Adverb
clastic	No	Yes	No	No
clastic rock	Yes	No	No	No

clastic (noun)	clastic rock (noun)
	(geology) a rock composed of broken pieces of older rocks

clastic (adjective)	clastic rock (adjective)
capable of being taken apart
of or belonging to or being a rock composed of fragments of older rocks (e.g., conglomerates or sandstone)