Ad·zhar·i·a or A·jar·i·a (ə-jär'ē-ə) An autonomous republic of southwest Georgia bordering on the Black Sea and Turkey. Colonized by the Greeks in the fourth and fifth centuries B.C., the region was ruled by the Romans and the Turks before its acquisition by Russia in 1878. Ad·zhar' (ə-jär') n., Ad·zhar'i·an adj. & n.