SRS, I’m not sure what you mean by a three way switch. In UK domestic lighting, we have one way and two way switches, the latter allowing the light to be switched from 2 points. Adding switching points in between is possible and the switch used to do that is, as far as I know, usually referred to as an intermediate switch. This page explains things UK wise and says an intermediate switch could be used as a one way switch.

An annoyance with UK lighting wiring btw is that (unless they have changed with more modern houses) is that they don’t usually run a neutral wire to the switch. This limits the choices when looking to use home automation switches like z-wave ones.