Is there a word for inserting a random line from a different language during a conversation?

Question

I think there might not be a word specifically for this, but there may be a more general word that covers all case where you switch from one language to another during a conversation or in writing. I suspect that it is the case, because you encounter it in writing and in countries where people use more than one language.

For example:

"I am aware that ce n'est pas vraie, but I would still caution prudence." said Roberto to his friend Mathieu.

Answer 1

I think this is what you’re looking for: https://en.m.wikipedia.org/wiki/Code-switching

In linguistics, code-switching or language alternation occurs when a speaker alternates between two or more languages, or language varieties, in the context of a single conversation.