dura mater Meaning, Definition & Usage

  1. noun the outermost (and toughest) of the 3 meninges
    dura.

WordNet

Du"ra ma"ter
Etymology
L., lit., hard mother. The membrane was called mater, or mother, because it was formerly thought to give rise to every membrane of the body.
Definitions
  1. (Anat.) The tough, fibrous membrane, which lines the cavity of the skull and spinal column, and surrounds the brain and spinal cord; -- frequently abbreviated to dura.

Webster 1913