Flint is a very hard type of rock. Ever since humans first learned to make tools, back in the Stone Age, they've used flint.

Through history, flint has been used for sharp tools, in walls and buildings, for making sparks to start fires, and in jewelry and pottery. You can also use the word figuratively, to mean a quality of hardness or even cruelty in a someone's personality: "The flint in his nature made him unsympathetic even to the most pitiful crying child."

Definitions of flint
  1. noun
    a hard kind of stone; a form of silica more opaque than chalcedony
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    the piece of flint that provides the igniting spark in a flintlock weapon
    a piece of flint that is struck to light a fire
    pebbles of flint used in masonry construction
    type of:
    silica, silicon dioxide, silicon oxide
    a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechatelierite
  2. adjective
    showing unfeeling resistance to tender feelings
    synonyms: flinty, granitic, obdurate, stony
    hardhearted, heartless
    lacking in feeling or pity or warmth
Word Family

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