Harold,
I've never heard the term "3-point switch" used here, but it may have been in the very early days. All the 1930s text books I have refer to "2-way" switches and nothing else.
In general electronics work we have various styles of multi-way switches (slide, rotary, toggle, etc.) and we follow the same general nomenclature, i.e. a 3-way rotary switch is one which has 3 positions.
