DICT.TW Dictionary Taiwan

 Wa·ter ham·mer Physics
 1. A vessel partly filled with water, exhausted of air, and hermetically sealed. When reversed or shaken, the water being unimpeded by air, strikes the sides in solid mass with a sound like that of a hammer.
 2. A concussion, or blow, made by water in striking, as against the sides of a pipe or vessel containing it.
 3. A metal hammer used when heated, as by dipping in hot water, to blister the skin, as for counterritation.
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 water hammer
      n : the banging sound of steam in pipes