tectum
/ˈtektəm/noun
1- Anatomy the uppermost part of the midbrain, lying to the rear of the cerebral aqueduct【剖】顶盖。
1.1
- （全称optic tectum）a rounded swelling (colliculus) forming part of this and containing cells involved in the visual system视觉盖。
词源
early 20th cent.: from Latin, literally 'roof'.