It is called a solid.
Solid nitrogen is called "nitrogen ice" or "nitrogen snow".
Solid form water is called ice.
When a solid turns into a liquid due to heating, it is called melting.
Conversion on of gas into solid is called desublimation.
A phase change from solid directly to gas is called sublimation. A common example of sublimation is that of dry ice (solid carbon dioxide).
Idol
A decaredra is the ten face solid figure.
Idols
A side of a solid figure is called a face.
According to my son's math homework a flat surface on a solid is called a face
A plane.
It's called a face
A decaredra is the ten face solid figure.
Idol
octagonal prism
The 7-faced solid is called a "hexagonal pyramid."
The crust is the solid surface of the Earth.