Meaning of MEDULLARY SHEATH

Pronunciation:			'med`lereesheeth
WordNet Dictionary
	Definition:		[n]  a layer of myelin encasing (and insulating) the axons of medullated nerve fibers
	Synonyms:		myelin sheath
	See Also:		axolemma, case, medulla, medullated nerve fiber, myelin, myelinated nerve fiber, myeline, nodes of Ranvier, oligodendria, oligodendroglia, Ranvier's nodes, sheath