Etymology and terminology
The English terms tram and tramway are derived from the Scots word tram, referring respectively to a type of truck (goods wagon or freight railroad car) used in coal mines and the tracks on which they ran. The word tram probably derived from Middle Flemish trame ("beam, handle of a barrow, bar, rung"). The identical word la trame with the meaning "crossbeam" is also used in the French language. Etymologists believe that the word tram refers to the wooden beams the railway tracks were initially made of before the railroad pioneers switched to the much more wear-resistant tracks made of iron and, later, steel. The word Tram-car is attested from 1873.
Although the terms tram and tramway have been adopted by many languages, they are not used universally in English; North Americans prefer streetcar, trolley, or trolleycar. The term streetcar is first recorded in 1840, and originally referred to horsecars. When electrification came, Americans began to speak of trolleycars or later, trolleys. A widely held belief holds the word to derive from the troller (said to derive from the words traveler and roller), a four-wheeled device that was dragged along dual overhead wires by a cable that connected the troller to the top of the car and collected electrical power from the overhead wires; this portmanteau derivation is, however, most likely folk etymology. "Trolley" and variants refer to the verb troll, meaning "roll" and probably derived from Old French, and cognate uses of the word were well established for handcarts and horse drayage, as well as for nautical uses.
The alternative North American term 'trolley' may strictly speaking be considered incorrect, as the term can also be applied to cable cars, or conduit cars that instead draw power from an underground supply. Conventional diesel tourist buses decorated to look like streetcars are sometimes called trolleys in the US (tourist trolley). Furthering confusion, the term tram has instead been applied to open-sided, low-speed segmented vehicles on rubber tires generally used to ferry tourists short distances, for example on the Universal Studios backlot tour and, in many countries, as tourist transport to major destinations. The term may also apply to an aerial ropeway, e.g. the Roosevelt Island Tramway.
Although the use of the term trolley for tram was not adopted in Europe, the term was later associated with the trolleybus, a rubber-tyred vehicle running on hard pavement, which draws its power from pairs of overhead wires. These electric buses, which use twin trolley poles, are also called trackless trolleys (particularly in the northeastern US), or sometimes simply trolleys (in the UK, as well as in Seattle and Vancouver).
The New South Wales, Australia, government has decided to use the term "light rail" for their trams.