Definitions of heater
  1. noun
    device that heats water or supplies warmth to a room
    synonyms: warmer
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    brasier, brazier
    large metal container in which coal or charcoal is burned; warms people who must stay outside for long times
    a space heater that transfers heat to the surrounding air by convection
    defroster, deicer
    heater that removes ice or frost (as from a windshield or a refrigerator or the wings of an airplane)
    heater that removes mist from the windshield of a car
    gas heater
    a heater that burns gas for heat
    heating pad, hot pad
    heater consisting of electrical heating elements contained in a flexible pad
    kerosene heater, kerosine heater, oil heater, oilstove
    heater that burns oil (as kerosine) for heating or cooking
    heater consisting of a series of pipes for circulating steam or hot water to heat rooms or buildings
    solar heater
    a heater that makes direct use of solar energy
    space heater
    heater consisting of a self-contained (usually portable) unit to warm a room
    any heating apparatus
    hot-water heater, hot-water tank, water heater
    a heater and storage tank to supply heated water
    electric fire, electric heater
    a small electric space heater
    a portable brazier that burns charcoal and has a grill for cooking
    water back
    water heater consisting of a tank or pipes set at the back of a fireplace or in the firebox of a stove
    type of:
    an instrumentality invented for a particular purpose
  2. noun
    (baseball) a pitch thrown with maximum velocity
    synonyms: bullet, fastball, hummer, smoke
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    a fastball that curves slightly away from the side from which it was thrown
    type of:
    delivery, pitch
    (baseball) the act of throwing a baseball by a pitcher to a batter
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