z-bedhttp://www.oed.com/dictionary/z-bed_n%3Ftab%3Dmeaning_and_useZ-bed, n.
First published 2005

Z-bednoun

Chiefly British (also with lower-case initial).
  1. 1973–
    A type of occasional bed with a three-part metal frame which folds up for storage; (also more generally) any of various types of portable folding bed; cf. zedbed n.
    1. 1973
      For sale: 1970 VW Bus with sun roof and Z-bed.
      Oshkosh (Wisconsin) Daily Northwestern 20 September 31/2 (advertisement)
    2. 2001
      ‘I'd rather sleep on the floor than share with Joe’, said David, hurling himself onto the damp Z-bed under the window.
      L. Voss, To be Someone 174

Originally published as part of the entry for Z, n.

Z-bed, n. was first published in 2005.