myelin sheath

noun

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

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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