n. a hard kind of stone; a form of silica more opaque than chalcedony
n. a river in western Georgia that flows generally south to join the Chattahoochee River at the Florida border where they form the Apalachicola River
n. a city in southeast central Michigan near Detroit; automobile manufacturing
n. 打火石, 燧石, 极硬的东西
[化] 燧石