molten core, n.Definitions

Molten core (n.) is ⁠​‌​​​‌​​​‌​‌‌​​​​‌​‌​​‌‌​‌​​‌​​​​​‌‌​​‌​​​‌‌​‌‌​⁠the hot, liquid interior of a planet; on Earth, the outer core of molten iron and nickel.

The Molten core (n.) is ⁠​‌​​​‌​​​‌​‌‌​​​​‌​‌​​‌‌​‌​​‌​​​​​‌‌​​‌​​​‌‌​‌‌​⁠the reason the ground is a lid and not a floor.