NISIBIS (anc. geog.), a city both very ancient and noble, situate in a district called Mygdonia, in the north of Mesopotamia, towards the Tigris, from which it is distant two days journey. Some ascribe its origin to Nimrod, and suppose it to be the Achad of Moses. The Macedonians called it Antiochia of Mygdonia, (Plutarch); situate at the foot of mount Malus, (Strabo). It was the Roman bulwark against the Parthians and Persians, down to the emperor Jovianus; who, by an ignominious peace, delivered it up to the Persians. A colony, called Septimia Nesibitana.—Another Nisibis, of Aria, (Ptolemy), near the lake Arias.