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myelin sheath

noun

Definition of myelin sheath

  1. :  a layer of myelin surrounding the axons of some neurons —called also medullary sheath



1891

First Known Use of myelin sheath

1891


Medical Dictionary

myelin sheath

noun

Medical Definition of myelin sheath

  1. :  the insulating covering that surrounds an axon with multiple spiral layers of myelin, that is discontinuous at the nodes of Ranvier, and that increases the speed at which a nerve impulse can travel along an axon—called also medullary sheath




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