1. a device (such as a pan filled with hot coals or water) used to warm a bed before getting into it
Usage: historical; chiefly British
2. a person or animal that shares a bed to provide warmth
Usage: informal

Examples

• In medieval times, servants would use a bedwarmer filled with hot coals to heat the master's bed.
• The old brass bedwarmer hung on the wall as a decorative reminder of the past.
• On cold winter nights, the family dog served as a faithful bedwarmer.
• Before electric blankets were invented, bedwarmers were essential household items.
• She filled the ceramic bedwarmer with hot water and slipped it under the sheets.