cornerstone vs building

cornerstone and building both are nouns.

Word	Noun	Adjective	Verb	Adverb
cornerstone	Yes	No	No	No
building	Yes	No	No	No

cornerstone (noun)	building (noun)
a stone at the outer corner of two intersecting masonry walls	the act of constructing something
a stone in the exterior of a large and important building; usually carved with a date and laid with appropriate ceremonies	the commercial activity involved in repairing old structures or constructing new ones
the fundamental assumptions from which something is begun or developed or calculated or explained	a structure that has a roof and walls and stands more or less permanently in one place
	the occupants of a building