1. a bed consisting of a water-filled mattress, typically made of vinyl, that conforms to the body’s shape

Examples

• They bought a waterbed for their new bedroom.
• The waterbed was popular in the 1970s and 1980s.
• She had trouble getting comfortable on the waterbed at first.
• The waterbed required a special heater to maintain the right temperature.
• Moving a waterbed is difficult because it weighs so much when filled.
• The waterbed developed a small leak and had to be repaired.