Washroom vs. bathroom: I’ve always found it strange to call a room a “bathroom” if it doesn’t have a shower or tub. On the other hand, most single-family homes in Canada have a “powder room” where people can wash their face and hands. Although these facilities serve similar purposes, the former is used for public spaces, while the latter is found inside homes.
As an Australian I always find it funny going places and having to remember which dance-around word everyone uses for "toilet". Washroom, restroom, bathroom, there's so many!
“Toilette” is still used that way in normal everyday French. “Je fais ma toilette” - I’m washing up/getting ready/getting dressed/doing my morning hygiene routine/etc.
The easy to remember terms and will work nearly anywhere without giving offence are: "loo" in a residential property or "gents/ladies" for a non-residential property.
Soviet apartments had a separate rooms for the toilet and the area with a bath/shower/sink. The area behind the toilet was usually a hinged wall that could be opened to reveal the entry point for utilities.
I assume toilet hands were an unspoken issue, because there was no possible way to traverse from the toilet room to the washroom without touching anything.
For a complete tangent, I’ll mention that Soviet toilets had a “poop shelf” so that people could eyeball their stool to gauge their health. One flaw of this design is that there was no odour suppression offered by toilets that immediately immerse stool in water.
This one (among others) does really fascinate me. Maybe it’s due to spending a lot of time around diverse groups of people but I’ve never really seen a huge distinction between these words. Washroom, bathroom, toilet, I and everyone I know pretty much would use interchangeably? Or at least wouldn’t blink at someone else using them.
Restroom, and a variety of others, might be slightly more usage specific but still… wouldn’t be unexpected or weird, I’d say?