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medullation

American  
[med-l-ey-shuhn, mej-uh-ley-] / ˌmɛd lˈeɪ ʃən, ˌmɛdʒ əˈleɪ- /

noun

Biology.

  1. the formation of a medullary sheath about a nerve fiber.

Etymology

Origin of medullation

medull(a) + -ation

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.