I have morphisms:
$$ f : A \to B \\ g : B \to C $$
The composition is:
$$ g \circ f : A \to C $$
In the function $(g \circ f)$ we call $A$ the domain and $C$ the codomain (or range).
I'm working in Haskell code, and in my application the type we pass through $(B)$ is particularly important. Does this intermediate value have a standard name?