SG Heritage Dictionary

Pineal [Adjective] Webster's Dictionary 1828

The pineal gland is a part of the brain, about the bigness of a pea, situated in the third ventricle; so called from its shape. It was considered by Descartes as the seat of the soul.

Pineal [Adjective] Webster's Dictionary 1913

Of or pertaining to a pine cone; resembling a pine cone.