The sieve bone
Ethmoid bone · os ethmoidale
A delicate, honeycombed bone between your eyes that forms the roof of your nose.
What it does
The ethmoid bone is a lightweight box of thin plates and air cells tucked between the eye sockets. Its top plate is riddled with tiny holes that let the nerves of smell pass from the nose into the skull. Its sides form the walls of the eye sockets and its middle forms part of the nasal septum.
Surprising fact
The name means "sieve-like" in Greek, after the dozens of tiny holes in its roof that the smell nerves thread through.
Why it matters
A hard knock to the face can crack this thin roof, which can damage the sense of smell or let fluid leak from around the brain into the nose.
Nearby
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Sources
Drafted with AI help; awaiting a human fact-check against these sources.
Open in the 3D atlas · Suggest a correction · Not medical advice.
3D models: Z-Anatomy & BodyParts3D (CC BY-SA 4.0 / 2.1 JP). Card text CC BY 4.0.