All surviving forms of modern Greek, except the Tsakonian language, are descendants of the common supra-regional (koiné) as it was spoken in late antiquity.

As such, they can ultimately be classified as descendants of Attic Greek, the dialect spoken in and around Athens in the classical era.

A Jewish dialect of Greek (Ρωμανιώτικη διάλεκτος) spoken by the Romaniotes, Yevanic is almost completely extinct today.

It has been legally recognised as the official language of the Deaf Community in Greece and is estimated to be used by about 42,000 signers (12,000 children and 30,000 active adult users) in 1986.

Unlike the recent immigrants from Albania, the Arvanites are a centuries-old local Albanian-speaking Greek community living in parts of Greece especially in the south.

In Greece, Slavic dialects heteronomous with standard Bulgarian and Macedonian are spoken; however, the speakers do not all identify their language with their national identity.

[6] In addition, there are an estimated 30,000 native speakers of Bulgarian in Western Thrace according to Ethnologue,[7] where it is referred to as Pomak.

Ladino, the Judeo-Spanish language, was traditionally spoken by the Sephardic community in Greece, particularly in the city of Thessaloniki, where, at their peak percentage, they made up 56% of the population.

[8] However, many of Greece's Jews were murdered in World War II, and a large number emigrated to Israel after 1948.

In the population of 200,000 to 300,000 Roma, or Gypsy, people in Greece today, the Romani language is spoken widely.

The dialect spoken in Greece (as well as in Bulgaria, Albania, North Macedonia, Moldova, Montenegro, Serbia, Romania, parts of Turkey, and Ukraine) is known as Balkan Romani.

Russian is also spoken as a second or third language by many Georgians and Pontic Greeks from Georgia, Ukraine, and Russia who settled in Greece in large numbers in the same period.

Traditionally, there were many more Turkish speakers in Greece, due to the long period of Ottoman rule.

[citation needed] Georgian is widely spoken particularly in Thessaloniki and other parts of Greek Macedonia by economic migrants who settled in Greece in the 1990s.