medullary sheath

noun

: myelin sheath

Word History

First Known Use

circa 1846, in the meaning defined above

Time Traveler
The first known use of medullary sheath was circa 1846

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“Medullary sheath.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/medullary%20sheath. Accessed 3 Mar. 2025.

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Medical Definition

medullary sheath

noun
: myelin sheath
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