hot bag

Noun

hot bag (plural hot bags)

1. A bag designed to generate and/or hold heat, used as a hot compress or warming device.
   • The exact effect of the fomentation may be secured by wrapping a hot bag with a moist flannel cloth .1904, John Harvey Kellogg ·, Rational Hydrotherapy, page 812
   • Think of having a hot water bag which you can take up at any time and by simply removing the stopper have instantly a hot bag that will give off a dry, even heat for hours longer than an ordinary bag filled with water.1906, “The Improved Heat-Storing Bag”, in The Voice of the Retail Druggist, volume 1, page 369
2. A bag for keeping pizza hot during delivery.
   • The latest hot bag innovation is based on the same technology that enabled the Thermos bottle to keep soup hot for generations of school children.2004, Pizza Today - Volume 22, Issues 7-12, page 57
   • Domino's HeatWave hot bags were introduced in 1998 to keep pizzas oven-hot during normal delivery. Originally, each hot bag contained a patented heating mechanism charged by plugging into an electric outlet at the store.2012, Alok Kumar Rai, Customer Relationship Management, page 228
3. Used other than figuratively or idiomatically: see hot, bag.