mesencephalon

The midbrain.

The midbrain; a segment of the encephalon consisting essentially of the corpora quadrigemina or optic lobes and the crura cerebri. See brain. Also mesencephal, mesocephalon.

The middle segment of the brain; the midbrain. Sometimes abbreviated to mesen. See brain.

A part of the brain located rostral to the pons and caudal to the thalamus and the basal ganglia, composed of the tectum (dorsal portion) and the tegmentum (ventral portion).

the middle portion of the brain