Dictionary entry

Myelin

Webster's Dictionary 1913

My″e‐lin (?), n.(Physiol. Chem.) (a) A soft white substance constituting the medullary sheaths of nerve fibers, and composed mainly of cholesterin, lecithin, cerebrin, albumin, and some fat. (b) One of a group of phosphorized principles occurring in nerve tissue, both in the brain and nerve fibers.