heater

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. An apparatus that heats or provides heat.
2. n. One who heats something or tends a heating apparatus.
3. n. Slang A pistol.
4. n. Baseball A fastball.

Century Dictionary and Cyclopedia

1. n. One who or that which heats.
2. n. Specifically— A furnace, stove, or other device for heating, drying, or warning buildings, rooms, drying-houses, fruit-evaporators, or parts of machines, as the calendering-rolls of a paper-mill.
3. n. A small mass of cast-iron designed to be heated and then placed in a hollow fiat-iron or in a coffee-pot, to heat the iron or keep the coffee hot.
4. n. In a sugar-making plant, a pan used for the first heating of the cane-juice or syrup; a heating-pan.
5. n. In electricity, that part of the Nernst lamp which, in starting, is heated by the electric current and by its heat starts the glower. See Nernst lamp.

Wiktionary

1. n. A device that produces and radiates heat, typically to raise the temperature of a room or building.
2. n. dated, slang A gun.
3. n. baseball (slang) A fastball.
4. n. gambling (slang) An extended winning streak.

GNU Webster's 1913

1. n. One who, or that which, heats.
2. n. Any contrivance or implement, as a furnace, stove, or other heated body or vessel, etc., used to impart heat to something, or to contain something to be heated.
3. n. slang A pistol or other carryable firearm.

WordNet 3.0

1. n. device that heats water or supplies warmth to a room
2. n. (baseball) a pitch thrown with maximum velocity