Definition of "flint"

A hard, fine-grained quartz that fractures conchoidally and generates sparks when struck against a material such as steel, because tiny chips of the steel are heated to incandescence and burn in air.  examples

A piece of flint, such as a gunflint, used to produce a spark by striking it with a firestriker.  examples

A small cylinder of some other material of the same function in a cigarette lighter, etc.  examples

A type of maize/corn with a hard outer hull.  examples

(figurative) Anything figuratively hard.  examples

(transitive) To furnish or decorate an object with flint.  examples