I think the term for this is Sprachbund[1] - where a number of languages in close geographical proximity pick up each others' grammatical and other traits despi

I think the term for this is Sprachbund[1] - where a number of languages in close geographical proximity pick up each others' grammatical and other traits despite belonging to different families. [1] https://en.wikipedia.org/wiki/Sprachbund https://en.wikipedia.org/wiki/Sprachbund