What is the meaning of Pillow?

A soft cushion used to support the head in bed.

Any similar head support used for sleep, such as a neck pillow or a hard porcelain pillow.

A pillow lava.

A piece of metal or wood, forming a support to equalize pressure; a brass; a pillow block.

A block under the inner end of a bowsprit.

The socket of a pivot.

A kind of plain, coarse fustian.

To rest as on a pillow.

Source: wiktionary.org