Definitions for "Substantia"
Latin = a substance.
L. substantia, essence, substance, material. Substantia gelatinosa of Rolandi was first described by Luigi Rolando (1773 -1831), an Italian anatomist, as a formation of a peculiar transparent substance at the tip of the posterior horn of the spinal cord. Substantia nigra is a pigmented area in the mid-brain described by Soemmering (1755 -1830).
nigra substantia (substance), nigra (black).