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Definition of molecular layer in US English:
molecular layer
noun
1A layer of molecules.
2Histology. Any of several layers of neural tissue composed chiefly of the terminal branchings of axons and dendrites, with relatively few cell bodies (also called plexiform layer); especially (a) either of two such layers of the retina; (b) the outermost layer of the cerebral and cerebellar cortex.
Origin
Mid 19th century; earliest use found in Scientific American. From molecular + layer.
