1560s, originally the flat stone atop a grave (or the lid of a stone coffin); from tomb + stone (n.). Meaning "gravestone, headstone" is attested from 1711. The city in Arizona, U.S., said to have been named by prospector Ed Schieffelin, who found silver there in 1877 after being told all he would find there was his tombstone.[tombstone etymology, tombstone origin, 英语词源]