myelin sheath

American  

noun

Anatomy.

1. a wrapping of myelin around certain nerve axons, serving as an electrical insulator that speeds nerve impulses to muscles and other effectors.

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Etymology

Origin of myelin sheath

First recorded in 1895–1900

Example Sentences

See Examples For:

myelin sheath

These precursor cells can mature into oligodendrocytes, which produce the myelin sheath surrounding axons.

From Science Daily ● Aug. 14, 2026

That timing appears to be essential for producing enough mature oligodendrocytes to properly restore the damaged myelin sheath.

From Science Daily ● Aug. 14, 2026

MS is a disease of the brain and central nervous system, in which the immune system mistakenly attacks the fatty myelin sheath that normally protects the nerves, like insulation around electric wires.

From BBC ● May 29, 2026

Oligodendrocytes, the cells that produce myelin to insulate nerve fibers, expressed fewer genes required for maintaining and regenerating the myelin sheath.

From Science Daily ● Nov. 24, 2025

However, EBV infection has been linked to several diseases, including MS: an incurable, chronic autoimmune disease that causes the body's immune system to attack the myelin sheath of neurons in the brain and nervous system.

From Science Daily ● May 28, 2024