Abounds in all the plains and valleys of the wilderness of the forty years' wanderings. In Isaiah 50:7 and Ezek. 3:9 the expressions, where the word is used, means that the "Messiah would be firm and resolute amidst all contempt and scorn which he would meet; that he had made up his mind to endure it, and would not shrink from any kind or degree of suffering which would be necessary to accomplish the great work in which he was engaged." (Comp. Ezek. 3:8, 9.) The words "like a flint" are used with reference to the hoofs of horses (Isaiah 5:28).

Noah Webster's New International Dictionary of the English Language

1. (n.) A massive, somewhat impure variety of quartz, in color usually of a gray to brown or nearly black, breaking with a conchoidal fracture and sharp edge. It is very hard, and strikes fire with steel.

2. (n.) A piece of flint for striking fire; -- formerly much used, esp. in the hammers of gun locks.

3. (n.) Anything extremely hard, unimpressible, and unyielding, like flint.