I generally use the format <Room> <Device> in order to give devices unique names that work outside the context of rooms. With Google, I find things work best if the device name ENDS with the name or type of device - switch, motion, light, temperature, TV, printer, fan, white laptop and so on. Just using that bit of the name is often enough for Google to work out which device you mean, particularly if you don't have more than one per room.