gritrock vs sandstone

gritrock and sandstone both are nouns.

Word	Noun	Adjective	Verb	Adverb
gritrock	Yes	No	No	No
sandstone	Yes	No	No	No

As nouns, sandstone is a hypernym of gritrock; that is, sandstone is a word with a broader meaning than gritrock:

gritrock: a hard coarse-grained siliceous sandstone
sandstone: a sedimentary rock consisting of sand consolidated with some cement (clay or quartz etc.)

gritrock (noun)	sandstone (noun)
a hard coarse-grained siliceous sandstone	a sedimentary rock consisting of sand consolidated with some cement (clay or quartz etc.)