Strong's #6864: tsor (pronounced tsore)

from 6696; a stone (as if pressed hard or to a point); (by implication, of use) a knife:--flint, sharp stone.

Brown-Driver-Briggs Hebrew Lexicon:

tsôr

1) flint, hard pebble

1a) used as a knife

Part of Speech: noun masculine

Relation: from H6696

Usage:

This word is used 5 times:

 

Exodus 4:25: "Then Zipporah took a sharp stone, and cut off the foreskin of her son, and cast"
Joshua 5:2: "unto Joshua, Make thee sharp knives, and circumcise again"
Joshua 5:3: "And Joshua made him sharp knives, and circumcised the children of Israel"
Isaiah 5:28: "their horses' hooves shall be counted like flint, and their wheels like a whirlwind:"
Ezekiel 3:9: "As an adamant harder than flint have I made thy forehead: fear them not,"