[vfdfv]

A related idea is linguistic "compositionality"

https://en.wikipedia.org/wiki/Principle_of_compositionality

I don't have hard numbers, but I know from experience that a large share of multiword expressions are non-compositional (the meaning of the larger phrase can't be inferred from its constituents), so in that case thinking of them as "over-divided" makes sense to me.

[Nadya]

In linguistics, we call such phrases "idioms".

https://en.wikipedia.org/wiki/Idiom