(pl. -os)
1- an underground railway system in a city, especially Paris（尤指巴黎的）地铁。
1.1
- an underground train, especially in Paris（尤指巴黎的）地铁列车。
词源
early 20th cent.: from French métro, abbreviation of métropolitain （from Chemin de Fer Métropolitain 'Metropolitan Railway'）.