orbit

anatomy

Also known as: socket

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Last updated

July 1, 2026

Quick Summary

The term "orbit" has two primary meanings. In astronomy, it refers to the path an object takes as it travels completely around another celestial body, such as the moon orbiting the Earth.1

In anatomy, the orbit is the bony cavity within the skull that houses the eyeball. This cavity also contains the muscles that move the eye, the lacrimal gland (which produces tears), and the necessary blood vessels and nerves. The space within the orbit is filled with fatty tissue that cushions the eye and allows for free movement. Infections can spread into the orbit from nearby sinuses, causing swelling and protrusion of the eye. Conditions like Graves ophthalmopathy can also affect the orbit.23

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human eye
The orbit
The eye is protected from mechanical injury by being enclosed in a socket, or orbit, which is made up of portions of several of the bones of the skull to form a four-sided pyramid, the apex of which points back into the head. Thus,…
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The eye is protected from mechanical injury by being enclosed in a socket, or orbit, which is made up of portions of several of the bones of the skull to form a four-sided pyramid, the apex of which points back into the head. Thus,…
Read More

eye disease
The orbit and lacrimal apparatus
The orbit is the bony cavity in the skull that houses the globe of the eye (eyeball), the muscles that move the eye (the extraocular muscles), the lacrimal gland, and the blood vessels and nerves required to supply these structures. The…
Read More
The orbit is the bony cavity in the skull that houses the globe of the eye (eyeball), the muscles that move the eye (the extraocular muscles), the lacrimal gland, and the blood vessels and nerves required to supply these structures. The…
Read More