What is another word for subway system?
Pronunciation: [sˈʌbwe͡ɪ sˈɪstəm] (IPA) 
A subway system is a network of underground trains that provides transportation in large cities. There are several other synonyms for the term subway system, including metro, underground, tube, and rapid transit. The term "metro" is commonly used in Europe and refers to a larger underground train system that may also include above-ground sections. The word "underground" is often used in London and New York City and refers to a system that is entirely below ground. "Tube" is a term used in London to describe the underground train system, while "rapid transit" refers to a system that moves quickly and efficiently through a city.
