copestone vs capstone

copestone and capstone both are nouns.

Word	Noun	Adjective	Verb	Adverb
copestone	Yes	No	No	No
capstone	Yes	No	No	No

As nouns, copestone and capstone are synonyms defined as:

Other synonyms of copestone include coping stone, stretcher.

As nouns, copestone and capstone are synonyms defined as:

copestone and capstone: a final touch; a crowning achievement; a culmination

Other synonyms of copestone include finishing touch.

copestone (noun)	capstone (noun)
a stone that forms the top of wall or building	a stone that forms the top of wall or building
a final touch; a crowning achievement; a culmination	a final touch; a crowning achievement; a culmination