sciatic nerve

American  

noun

Anatomy.

1. either of a pair of nerves, the largest in the body, that originate in the sacral plexus of the lower back and extend down the buttocks to the back of the knees, where they divide into other nerves: the sciatic nerve and its branches innervate large areas of the pelvis, leg, and foot.

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sciatic nerve Scientific  

/ sī-ăt′ĭk /

1. A thick nerve that arises in the lower part of the spine and passes through the pelvis on its way to the back of the leg. It carries sensory information from the leg to the central nervous system and controls the action of many muscles. The sciatic nerve is the largest nerve in the body.

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Etymology

Origin of sciatic nerve

First recorded in 1735–45

Example Sentences

Sciatica is pain or numbness that follows the path of the sciatic nerve from the lower back down the leg.

From Barron's • Oct. 9, 2025

Using mouse antibodies that glom on to proteasomes, and other methods, the investigators found the proteasomes on the surface of neurons in the spinal cord, dorsal root ganglia, sciatic nerve and peripheral nerves innervating skin.

From Science Daily • Apr. 12, 2024

Sciatica is a condition that causes pain to spread “from the lower back through the hips and buttocks and down each leg” via the sciatic nerve, according to the Mayo Clinic.

From Los Angeles Times • Aug. 28, 2023

The sciatic nerve is the largest nerve in the body, and the irritation of that nerve that causes the pain better known as sciatica is usually a result of pressure from the bony spinal column.

From New York Times • Jan. 12, 2023

He used an electric current to stimulate an amphibian’s calf, then employed the galvanometer to measure how long it took the electrical current to run along the sciatic nerve.

From "A Deadly Wandering: A Mystery, a Landmark Investigation, and the Astonishing Science of Attention in the Digital Age" by Matt Richtel