me·dul·la (mĭ-dŭl'ə)
n., pl., -dul·las, or -dul·lae (-dŭl'ē).

1. The inner core of certain organs or body structures, such as the marrow of bone.
2. The medulla oblongata.
3. See myelin.
4. Botany.
   1. The pith in the stems or roots of certain plants.
   2. The central portion of a thallus in certain lichens and red or brown algae.

[Middle English, from Latin, perhaps alteration (influenced by medius, middle; see medial) of *merulla.]

medullar me·dul'lar or med'ul·lar'y (mĕd'l-ĕr'ē, mə-dŭl'ə-rē) adj.

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The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

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