medulla

noun, plural me·dul·las, me·dul·lae [muh–duhl-ee] /məˈdʌl i/.

1. Anatomy.
   1. the marrow of the bones.
   2. the soft, marrowlike center of an organ, as the kidney or adrenal gland.
   3. medulla oblongata.
2. Botany. the pith of plants.

noun plural -las or -lae (-liː)

1. anatomy
   1. the innermost part of an organ or structure
   2. short for medulla oblongata
2. botany another name for pith (def. 4)

n.hindmost segment of the brain, 1650s, from Latin medulla, literally “marrow,” also “pith of plants,” of unknown origin, perhaps related to or influenced by medius “middle” (but cf. also Old Irish smiur, Welsh mer “marrow”). The word was used in the Latin senses in Middle English. Related: Medular; medullary. n. pl. me•dul•las

1. The inner core of certain organs or body structures, such as the marrow of bone.medullary substance

Plural medullas medullae (mĭ-dŭl′ē)

1. See medulla oblongata.
2. The central portion of an anatomical structure, such as the adrenal gland or the kidney.