Actually, there was no single Scythian language, but this classification is used when speaking about all Scythian and Samatian dialects existing on the Black Sea's northern shores from the 8th century B.C. to the 5th century A.D. The early, more archaic forms of this speech can be called Scythian while the late ones were spoken by Sarmatian tribes. Scythian and another minor language, Alanian, were the predecessors of the modern Ossetic language.
There are no written texts in any variant. The only materials are toponimic names, tribal and personal names found on Greek inscriptions in the ruins of ancient Black Sea colonies (Panticapeus, Olvia, etc.) We know about 200 word stems in Scythian, and that, certainly, has to be deemed paltry. A key for analysis of them is found in material from the Ossetic language.
The grammatical structure has not been researched enough, but its descent
from Iranian is evident. Some traits of phonetics are also known, as well
as syntactic features. All, to repeat, have an Iranian genesis.