flint

noun

1. a hard stone, a form of silica resembling chalcedony but more opaque, less pure, and less lustrous.
2. a piece of this, especially as used for striking fire.
3. a chunk of this used as a primitive tool or as the core from which such a tool was struck.
4. something very hard or unyielding.
5. a small piece of metal, usually an iron alloy, used to produce a spark to ignite the fuel in a cigarette lighter.

verb (used with object)

6. to furnish with flint.

noun

1. Austin,1812–86, U.S. physician: founder of Bellevue and Buffalo medical colleges.
2. his sonAustin,1836–1915, U.S. physiologist and physician.
3. a city in SE Michigan.
4. Flintshire.

noun

1. an impure opaque microcrystalline greyish-black form of quartz that occurs in chalk. It produces sparks when struck with steel and is used in the manufacture of pottery, flint glass, and road-construction materials. Formula: SiO 2
2. any piece of flint, esp one used as a primitive tool or for striking fire
3. a small cylindrical piece of an iron alloy, used in cigarette lighters
4. Also called: flint glass, white flint colourless glass other than plate glass
5. See optical flint

verb

6. (tr) to fit or provide with a flint

noun

1. a town in NE Wales, in Flintshire, on the Dee estuary. Pop: 11 936 (2001)
2. a city in SE Michigan: closure of the car production plants led to a high level of unemployment. Pop: 120 292 (2003 est)

1. A very hard, gray to black variety of chalcedony that makes sparks when it is struck with steel. It breaks with a conchoidal fracture.
2. The dark gray to black variety of chert.