tectumPronunciation: /ˈtɛktəm/Definition of tectum noun Anatomy the uppermost part of the midbrain, lying to the rear of the cerebral aqueduct. (in full optic tectum) a rounded swelling (colliculus) forming part of the tectum and containing cells involved in the visual system. Origin: early 20th century: from Latin, literally 'roof'tectum in other Oxford dictionaries Definition of tectum in the US English dictionary
