neu·​ri·​lem·​ma ˌnu̇r-ə-ˈle-mə How to pronounce neurilemma (audio)
: the plasma membrane surrounding a Schwann cell of a myelinated nerve fiber and separating layers of myelin
neurilemmal adjective

Word History


alteration (after Greek lémma "peel, rind, husk" as in sarcolemma and other terms) of New Latin neurīlēma, from Greek neur- neur- + eílēma "veil, covering, wrapper," from eilē-, variant stem of eileîn "to wind, turn round, rollup" + -ma, resultative noun suffix — more at welter entry 1

Note: The Latin term neurilema was introduced by the German physician and anatomist Johann Christian Reil (1759-1813) in Exercitationum anatomicarum fasciculus primus, De structura nervorum (Halle, 1796), p. 1. Reil states that he prefers the Greek-derived word neurilema because the Latin expression tunica nervosa or nervea seems to afford an indirect sense—"covering made of nerve matter"—whereas his intended sense is presumably "covering of the nerve." The term was taken up as névrilème by the French anatomist Xavier Bichat in Anatomie générale, appliqué à la physiologie et à la médecine, première partie, tome premier (Paris, 1801), p. 137 passim.

First Known Use

1852, in the meaning defined above

Time Traveler
The first known use of neurilemma was in 1852

Dictionary Entries Near neurilemma

Cite this Entry

“Neurilemma.” Dictionary, Merriam-Webster, Accessed 17 Jun. 2024.

Medical Definition


neu·​ri·​lem·​ma ˌn(y)u̇r-ə-ˈlem-ə How to pronounce neurilemma (audio)
variants also neurolemma
: the outer layer surrounding a Schwann cell of a myelinated axon

called also nerve sheath, Schwann's sheath, sheath of Schwann

neurilemmal adjective
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