I'm interested in formalising/documenting a program plotting Venn charts (well UpSet plots actually). Is there a term that can unambiguously refer to the coloured partition of the visualisation below (obtained from Wolfram alpha from $A \cap B \setminus C$) in relation to $A$ and $B$? It was previously referred to as distinct intersection of $A$ and $B$ (because it does not include the intersection of $A$ and $B$ with any other set) - is there a formal term for this concept?
Edit: in general I am interested in a case of $n$ sets. I am looking for a generic name for a region of an intersection of $k$ sets ($k \leq n$) such that it is exclusive to the sets forming the intersection this is it excludes overlap with any other set that do not for this $k$ intersection.