Cortex

How to spell cortex

6 letters · 2 syllables

How to pronounce cortex

Say the part in capitals loudest.

What does cortex mean?

1. nounThe outer layer of an organ or structure, especially the folded grey matter on the surface of the brain.

Cortex in a sentence

• The scan showed reduced activity in the visual cortex of the brain.

• The adrenal cortex produces several important hormones.

Where does cortex come from?

Language of origin: Latin

The word comes straight from the Latin cortex, which literally meant the bark of a tree or the rind of a fruit, the tough protective layer wrapped around the softer inside. Anatomists of the seventeenth and eighteenth centuries borrowed the term wholesale to describe the outer layer of an organ, reasoning that the surface of the brain or kidney covered the interior much as bark covers the wood beneath. English took it directly into scientific Latin around the early 1600s without translating it, which is why the spelling keeps its Latin shape so faithfully. The same root survives in the everyday word 'cork', since cork is harvested from the bark of the cork oak, and in 'cortisone', a hormone named for the adrenal cortex where it is produced. Because the word is a direct Latin loan, its plural is the Latin 'cortices', a form that can surprise writers expecting a simple added 's'.

How the word is built

• cortex (Latin for bark, rind, or outer shell); a whole-word borrowing with no separable prefix or suffix