noun ·Rare ·Advanced level

Definitions

Noun

1. 1
   A substance present in the protoplasm of the retinal epithelium cells, and resembling, if not identical with, the myelin that forms the medullary sheaths of nerve fibres. uncountable

Etymology

From myelin + -oid + -in.

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.