amyelination

[ā-mī′ə-lə-nāshən, ə-mī′-]

n.

Congenital absence of the myelin sheath on a nerve.

Related formsa•mye•li•nat′ed (-nā′tĭd) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.