metro

Word family

• metropolitan
  adjectiveB2
• metropolis
  nounB2
• metroplex
  nounC1

Synonym discussion

Sense: noun/1

All four words describe city train systems that run in tunnels, but each has a regional identity. 'Subway' is the standard term in most of the United States and Canada, as well as in many other countries (e.g. Beijing Subway). 'Underground' is the British English term, and 'the Underground' is the official name of London's system. 'Tube' is an informal British nickname for the London Underground, named for the round, tube-like tunnels. 'Metro' is the default term in Paris (Métro), Washington DC, and many other cities worldwide. In everyday usage, all four are correct — the key is knowing which term the local transit authority uses. For example: 'Take the subway in New York, but ride the metro in Montreal.'

Common collocations

Etymology

The word 'metro' is a shortened form of 'metropolitan,' which entered English through French from Latin 'metropolitanus.' The Latin word came from Greek 'metropolis' (μητρόπολις), meaning 'mother city' — a combination of 'mētēr' (mother) and 'polis' (city). The railway sense began in Paris in 1900, when the city opened the 'Chemin de Fer Métropolitain' (Metropolitan Railway), which Parisians quickly shortened to 'le métro.' The sense of 'metro' meaning 'a large city' comes from the same Greek root but developed independently through the shortening of 'metropolis' itself.