You're saying that it's idiomatic in some languages to say something that translates to "dad's mother-in-law" to refer to one's maternal grandmother?

What is the semantic difference between saying that and simply saying "maternal grandmother" (or just "grandmother")? Does it indicate something along the lines of "my grandmother" while also communicating distance from one's mother, or that one's mother has died?

Do you know of any other interesting relationship semantics that are frequently expressed in other languages, but awkward to say in English?