mater, matris, n
declension: 3, gender: F
1. lady, matron
2. mother, foster mother
3. origin, source, motherland, mother city
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du·ra ma·ter (dr mtr, mä-, dyr)
n.
The tough fibrous membrane covering the brain and the spinal cord and lining the inner surface of the skull. It is the outermost of the three meninges that surround the brain and spinal cord.
[Middle English, from Medieval Latin dra mter (cerebr), hard mother (of the brain), dura mater (translation of Arabic 'umm ad-dim a-figah, the dense mother of the brain, matrix of the brain) : Latin dra, feminine of drus, hard; see duramen