why is it called a restroom sign —

Founded why is it called a restroom sign models & stl files for printing
Its ancient Rome
chile1418
Maker sign
rOxANDtOl
no children sign
bitmeisterei
Caution sign
Bananaman
Stop sign
Orflo
Cardboard Sign
Prusalicinator
Letter A MMU
muddymaker
Caliper pen
jpb515
Minecraft Coaster
Sirprintsalot
heart crown
steven2
Toms Filament Mount
itsthejoker