Talysh is a "vulnerable" northwestern Iranian language. There's this word "ver" in this language which means something like "of high quantity" which is quite similar to English "very". I looked up etymology of "very" and apparently it comes from an Indo-European origin meaning "true". So my question is, how likely is it that these two Indo-European languages developed the same usage for "ver"? Or is it just a coincidence? (I'm no linguist and not even a native speaker of English or Talysh, so I apologize for any mistake that might exist in the question). Thanks in advance.
This isn't that strange, I don't think, although it's a semantic pathway that does not appear to have been looked at specifically very much by historical linguists. In many unrelated language families, you see semantic maps for particular lexical items where words related to ``truth'' or some other expression of epistemic mood (what the speaker knows or believes to be true) is associated with quantity.
You can see the pathway pretty clearly: Start with "This is true", then you use "true" for emphasis with size, like "that's truly big", then maybe with quantity, like "that's truly a lot of corn", then "truly" becomes an obligatory part of that expression and then later the primary expression of quantity, such that "that's truly corn" means "that's truly a lot of corn".
You actually see this in modern Bay Area English in California, where "hella" derived from an emphatic "hell of a", as in "that's a hell of a lot of apples", but the original part of the quantifying expression "a lot" was dropped and the emphatic came to itself represent the quantity, as in "that's hella apples", which means "that's a lot of apples".
Does PIE *wehros or even *weh have descendant anywhere in all of Indo-Iranian?
If not, seems unlikely.