Koina

The normal assumption that Τέταρτος is due to Doric or Attic influence and τέτορτος is the ‘correct’ form cannot be accepted a priori, but is supported by the presence of τέταρτος in a few Mantinean inscriptions written almost in Doric koina.

The documents from Kytenion are in North-west Greek koina:[…]

The Sicilian Hellenistic inscriptions, and especially the public ones, show a highly standardized language, which can be called Sicilian Doric koina. The Sicilian Doric koina was similar to other Doric koinas such as the koina of Rhodes, of the Achaean League, of north-western Greece, which were also especially used for public purposes. The existence of these Doric koinas is usually taken to indicate the resilience of the Doric-speaking areas to the encroachment of the Attic-based koine.

The terms ‘koina’ (in the singular) and ‘koinai’ (in the plural) were coined by ancient Greek scholars, but, unlike the term ‘koine’, they do not appear as such in any other genre of Greek texts, literary and epigraphic alike. As a general rule, dialectologists normally use the term ‘koina’ to refer to a local variant of koine or, in other words, to the admixture of koine and the dialect spoken in a particular Doric area. Thus, one of the essential features of a koina is the fact that it cannot be separated from koine, to the extent that the former is defined on the basis of the latter.