The notion of linguistic mediation should cover everything that can happen
when languages are in contact and there is some impulse for communication across
their boundaries. When we learn the language of the other, that is a form of mediation.
So is recourse to a pidgin, or to a lingua franca such as international English.
Mediation might also involve a conversation in several languages, as in the use of
passive knowledge of the other’s tongue, or the various forms of code-switching.