For the sake of this question, let's call types of words forms "onym"s, as in "demonym" or "retronym". (Note: I don't know the word for those kinds of words, either.)
I'm looking for the "onym" that means "pertaining to".
For example, literally is the __onym of literal. Functional is the __onym of function.
Does such a word exist?
Edit: Sorry, it doesn't actually have to end in "nym", I'm just not very good at articulating this sort of thing.