montagne russe
/mɒnˌtanjə ˈruːs/(also montagnes russes)
noun
A scenic switchback railway; a roller-coaster (also as the name for a particular attraction).
Origin
Mid 19th century; earliest use found in Blackwood's Magazine. From French montagnes russes roller-coaster, lit. ‘Russian mountains’ from the plural of montagne + russe Russian, with reference to the popularity in Russia of the winter sport.