DictionaryflintSpark-producing stone
noun

flint

FLINT/flɪnt/

A very hard stone that produces sparks when struck with steel.

The flint sends out sparks where it meets the steel.

Close-up of a chipped gray flint stone meeting a steel fire striker, with a few bright sparks issuing from the contact point.
Etymology

Old English flint already named stone distinguished by hardness and by giving off sparks when struck. The selected meaning preserves those same defining physical properties.

In context

Chronicle - Medieval History Documentaries20:13
I got my flint and my steel. Struck together, they spark. The trick though is to catch one of those sparks and to keep it alight.
What It Was Like To Live On A Medieval Farm As A Peasant | Tudor Monastery | Chronicle

More examples

  • They found a sharp piece of flint in the field.
  • An ancient tool had been chipped from flint.
  • He carried flint and steel for lighting fires.

Forms

flint · flints

flinty adjective — hard like flint

Similar words

chert
A broader closely related category of hard silica-rich rock.