Definition of tentorium in English:


nounPlural tentoria

  • 1Anatomy
    A fold of the dura mater forming a partition between the cerebrum and cerebellum.

    • ‘The straight sinus, located at the site of attachment of the falx cerebri to the tentorium cerebelli, has been opened.’
    • ‘Such a differentiation might not even be possible; as more is learned about the biological bases of mental illness, it appears that the tentorium is not the dividing line we once believed it to be.’
    • ‘The tentorium cerebelli is continuous with the posterior and anterior petroclinoid ligaments.’
    • ‘As he cuts away the tentorium, where the membrane sheathing the brain gathers and parts, he sees it as ‘a pale delicate structure of beauty, like the little whirl of a veiled dancer’.’
    • ‘The free front margin of the tentorium fits closely round the back of the brain stem; the brain stem can be damaged, for example if a tumour growing above or below the ‘tent’ encroaches on this narrow space.’
  • 2Entomology
    An internal skeletal framework in the head of an insect.

    • ‘Indeed, this family has various plesiomorphic features, such as a complete tentorium and a mouthcone that is nearly bilaterally symmetrical, and as such it is clearly a basal group of thrips.’
    • ‘More posterior head skeletal structures and the tentorium do not develop in these embryos.’


Early 19th century: from Latin, literally ‘tent’.