'Midbrain' definitions:

Definition of 'midbrain'

(from WordNet)
noun
The middle portion of the brain [syn: midbrain, mesencephalon]

Definition of 'Midbrain'

From: GCIDE
  • Midbrain \Mid"brain`\, n. [Mid, a. + brain.] (Anat.) The middle segment of the brain; the mesencephalon. See Brain. [1913 Webster]