The term is also sometimes used is relation to dominants, submissives, masters, and slaves, but it is notable that in these cases the person concerned doesn't usually switch with the same partner. For example, a person may be a dominant at all times with one partner and a submissive with a different partner. This is because in a longer-term relationship the power or authority dynamics tends to extend (and continue to be rewarding) outside the boundaries of simple scenes. To switch roles in such a situation would disrupt the underlying dynamic. It is easier, and often more satisfying, to establish a different power/authority dynamic with a different person.
Thus we might have a couple in a stable dominant/submissive relationship where the dominant partner occasionally engages as a submissive with another dominant or with a master to get their submissive needs met. In this case, the dominant might talk about "switching with their master."
This continuity of power/authority is typically absent between a top and bottom so they can switch roles without disrupting their dynamic.