Pipe

The term pipe is used to refer to hollow tubes used to move gas, liquids, or granulated solids, from one place to another.

Some tobacco users use a tobacco pipe to hold burning tobacco so they can inhale its smoke.

In geology a pipe is a solid instrusion of once molten rock, from the Earth's mantle, that has intruded into an older layer of rock. As these pipes cool they can produce valuable minerals, like crystals of diamond.