Vaso (Vasily) Ivanovich Abaev (Ossetian: ? ?; Russian: ? , also transliterated as Abayev and Abayti; 15 December 1900 – 18 March 2001) was an ethnically Ossetian Soviet linguist specializing in Iranian, particularly Ossetian linguistics.
Abaev was born in the village of Kobi, Georgia, Russian Empire. He studied at the Gymnasium of Tiflis in 1910-1918 and graduated from the Leningrad University in 1925. He studied Iranian philology under Friedman's direction and, as many other young linguists, fell under the influence of the controversial Nicholas Marr, joining Marr's Yaphetic Institute in 1928. After Marr's death, he moved to broad Iranian topics and field work in Ossetia until the end of World War II. In 1945 he moved back to Leningrad where he published his work on the Nart sagas, a dictionary and grammar book of Ossetian. With Joseph Stalin's condemnation of Marr's linguistic theories the Yaphetic Institute was purged, but Abaev was spared.
Starting with the 1950s, Abayev became internationally famous as the leading authority on Scythian and Sarmatian linguistics. Assisted by his friend, Georges Dumézil, Abaev demonstrated connections between the Scythian languages and modern Ossetian. He also pointed out some striking similarities between Ossetian and Celtic mythology.
His magnum opus, the Etymological Dictionary of Ossetian Language, which is based on the material of 190 languages and dialects, was published in four volumes between 1959 and 1989 and became known outside the USSR as well. He died at the age of 100 in Saint Petersburg. Several years later, a monument to him was unveiled in Tskhinval.