noun
1. : a tube inside a drill pipe and supported by a bit to receive the core in core boring
2. : a tube usually of iron on which a foundry loam core is formed
noun
1. : a tube inside a drill pipe and supported by a bit to receive the core in core boring
2. : a tube usually of iron on which a foundry loam core is formed
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012