tegmentum

/T EH1 G M EH1 N T AH0 M/
noun
  1. 1

    The ventral portion of the midbrain, divided from the tectum by the cerebral aqueduct and the periaqueductal grey

  2. 2

    Containing the following nuclei: red nucleus, substantia nigra, ventral tegmental area

Source: https://en.wiktionary.org/wiki/tegmentum