Phren

Phren (Ancient Greek: φρήν phrēn "mind", genitive: φρενός) is an Ancient Greek word for brain or mind. It is sometimes written later as "fren," and is found in the English language words schizophrenia, phrenitis, phrenic nerve, frenzy, frenetic.

Some ancient Greeks, including Aristotle, believed that the "phren" was located in the heart rather than the cranium.