hot water bag

• hot-water bag, hotwater bag

hot water bag (plural hot water bags)

1. (dated) A hot water bottle.
   • 1887, Oliver Wendell Holmes, chapter 1, in Our Hundred Days in Europe‎, Boston: Houghton Mifflin, page 20:

     Nothing is more comfortable, nothing, I should say, more indispensable, than a hot-water bag,—or rather, two hot-water bags; for they will burst sometimes, as I found out, and a passenger who has become intimate with one of these warm bosom friends feels its loss almost as if it were human.

   • 1931, Ethel Lina White, chapter 5, in Put Out the Light‎, London: Wark Lock:

     Presently her stiff limbs relaxed in the gentle heat from her hot water bags.

   • 1957, Neville Shute, On the Beach‎, New York: William Morrow:

     “I think he’s got flu, Mummy. He’s frightfully tired, for one thing. He’ll have to go to bed directly we get home. Could you light a fire in his room, and put a hot-water bag in the bed? […] ”