Graeco-Albanian

Graeco-Albanian or Albano-Greek is a proposed Indo-European subfamily – in the broader linguistic family known as (Palaeo-)Balkanic Indo-European – of which the only surviving representatives are Albanian and Greek. This Indo-European subfamily encompasses the Albanoid (Illyric) subbranch (Albanian and Messapic), and the Graeco-Phrygian subbranch (Greek and Phrygian). Within the Palaeo-Balkan branch this IE subfamily is separated from Armenian.

Graeco-Albanian potential innovations
Innovative creations of agricultural terms shared only between Albanian and Greek, such as *h₂(e)lbʰ-it- 'barley' and *spor-eh₂- 'seed', were formed from non-agricultural Proto-Indo-European roots through semantic changes to adapt them for agriculture. Since they are limited only to Albanian and Greek, they could be traced back with certainty only to their last common Indo-European ancestor, and not projected back into Proto-Indo-European.

Criticism
According to linguist Lucien van Beek – the author of the chapter "Greek" in the same book The Indo-European Language Family by Thomas Olander (ed., 2022) – a number of potential Greek and Albanian common innovations adduced in the chapter "Albanian" by Hyllested and Joseph "can or must be dated later than Proto-Greek", concluding that he is "not convinced of a close genetic relation between Greek and Albanian".