DEMYELINATION

Myelin is an electrically insulating phospholipid layer that surrounds the axons of many neurons. It is an outgrowth of glial cells: Schwann cells supply the myelin for peripheral neurons while oligodendrocytes supply it to those of the central nervous system. Myelin is considered a defining characteristic of the (gnathostome) vertebrates, but it has also arisen by parallel evolution in some invertebrates. Myelin was discovered in 1878 by Louis-Antoine Ranvier.
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Demyelination /de·my·elin·a·tion/ destruction, removal, or loss of the myelin sheath of a nerve or nerves. Called also myelinolysis. [more]Demyelination - Community and Resources

Noun
1. loss of the myelin covering of some nerve fibers resulting in their impaired function
(hypernym) degenerative disorder
(part-holonym) multiple sclerosis, MS, disseminated sclerosis, disseminated multiple sclerosis

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