Does servicio carry m/any of these meanings in English? Ex: The service (at a restaurant) was terrible. The (cell) service is great in that area. My aunt and my grandpa were both in the (military) service. His mother's china had (dinnerware) service for 8.
And if not, how do you express these other concepts?
It doesn't necessarily refer to the loo. Although there are signs stating "Los Servicios" for public toilets, I believe that servicio is a much more general term. It could be any kind of service: phone service, internet service, military service, service to your fellow humans, and so on.
If for some reason, you needed to discuss the actual toilet in your home in Spanish, it would be called "inodoro" for the toilet bowl itself. To talk about the room in your home in which this is located, I've usually heard "lavabo" or "baño." It's possible that there are some people who use the term "servicio" for the room inside their house that contains a toilet, but I haven't heard it used in that way.
On the other hand, it's common to see signs "Servicios Publicos" for public toilets/washrooms/restrooms. It's short for Servicios de Baños Publicos. Of course, they have toilets and not baths.
I never thought about that before. If I were to use "el servicio" I would only use it if I were asking about a public restroom such as in a restaurant although I would probably use "baño' or "lavabo" instead. If I were in someone's home, I would only use "baño." In Mexico, Central and South America I have never heard anyone use "el servicio." I believe that in Spain you will also hear "aseos." That is more like asking "Where are the toilets." Although the word I most hear for toilet is inodoro.
Yes, service can have many meanings. For example, as a noun, it can be used for: church service (servicio religioso), work provided (automobile, restaurant, etc.), organization (military, public), and a set of crockery. And I have seen it used to designate a public rest room. The verb servir also has many uses.