|Noah Webster's Dictionary|
1. (n.) The principal stone in a foundation; the chief or corner stone.
2. (n.) The stone at the head of a grave.
Int. Standard Bible Encyclopedia
Headstone (2 Occurrences)
2 Kings 23:17 What is that headstone I see over there? And the men of the town said to him, It is the resting-place of the man of God who came from Judah and gave word of all these things which you have done to the altar of Beth-el. (BBE)
Zechariah 4:7 Who art thou, O great mountain? before Zerubbabel thou shalt become a plain: and he shall bring forth the headstone thereof with shoutings, crying, Grace, grace unto it. (KJV BBE)