1. a room in a ship or building where a furnace or boiler is located and tended
Usage: nautical; also called firebox or boiler room
2. a room in a fire station where firefighters rest, eat, or socialize when not responding to calls
Usage: informal

Examples

• The engineer descended into the fireroom to check the boiler pressure.
• The ship's fireroom crew worked in intense heat shoveling coal into the furnace.
• Firefighters gathered in the fireroom to eat dinner between emergency calls.
• The fireroom of the old steamship was cramped and sweltering.
• During the night shift, the fireroom was quiet except for the hum of the heating system.