firestone has definitions from the fields of geology,chemistry
1
[ noun ] (chemistry,geology) a piece of flint that is struck to light a fire

Related terms

flint

2
[ noun ] Last name, frequency rank in the U.S. is 10231
3
[ noun ] (geology) a sandstone that withstands intense heat; used to line fireplaces and furnaces and kilns

Related terms

sandstone

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