If you ask where the bathroom is, TOIRE is fine. TOI L/RE (whoops, the T fell off)
In public places, temples and some restaurants, you may see signs pointing to O TE ARAI (the honorable hand-washing)
That's the toilet.

On the doors, you’ll see the characters for Man or Woman.
Or, just like here, clever, weird or just plain goofy silhouettes.

CHI KA TETSU = earth/ground under iron = subway

---