Source : Webster's Revised Unabridged Dictionary (1913)

Neurilemma \Neu`ri*lem"ma\, n. [NL., from gr. ? nerve + ? peel,
   skin.] (Anat.)
   (a) The delicate outer sheath of a nerve fiber; the primitive
       sheath.
   (b) The perineurium.

Source : WordNet®

neurilemma
     n : thin membranous sheath around a nerve fiber [syn: {neurolemma}]