waterbed

[ waw-ter-bed, wot-er- ]
/ ˈwɔ tərˌbɛd, ˈwɒt ər- /

noun

a bed having a liquid-filled rubber or plastic mattress in a rigid, often heated, waterproof frame, and providing a surface that conforms to the sleeper's body in any position.

Origin of waterbed

First recorded in 1835–45; water + bed
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for waterbed

  • Another novel feature was in the method of controlling the depth of submergence when navigating between the surface and waterbed.

    Aircraft and Submarines|Willis J. Abbot.
  • Built to further demonstrate the possibility of navigation over the waterbed of seas or the ocean.