couchette

noun3

1. •
   A compartment on a passenger train having berths for sleeping.

   • But I was disturbed to find a blot on my conception of the ultra-modern S.N.C.F.—the couchette car offered neither hot water nor, unless I looked in the wrong places, an electric razor point. — 1962
2. •
   A berth in such a compartment.
3. •
   (rare) A couch.