Definitions of H2O
  1. noun
    binary compound that occurs at room temperature as a clear colorless odorless tasteless liquid; freezes into ice below 0 degrees centigrade and boils above 100 degrees centigrade; widely used as a solvent
    synonyms: water
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    tap water
    water directly from the spigot
    bath water
    water used for a bath
    water in which dishes and cooking utensils are washed
    distilled water
    water that has been purified by distillation
    holy water
    water that has been blessed by a priest for use in symbolic purification
    ground water, spring water, well water
    underground water that is held in the soil and in pervious rocks
    hard water
    water that contains mineral salts (as calcium and magnesium ions) that limit the formation of lather with soap
    solution of calcium hydroxide in water used as an antacid
    melted snow or ice
    brine, saltwater, seawater
    water containing salts
    fresh water, freshwater
    water that is not salty
    partially melted snow
    soft water
    water that is not hard (does not contain mineral salts that interfere with the formation of lather with soap)
    bilge, bilge water
    water accumulated in the bilge of a ship
    water of crystallisation, water of crystallization, water of hydration
    the water present in hydrated compounds
    red tide
    seawater that is discolored by large numbers of certain dinoflagellates that produce saxitoxin
    rain, rainwater
    drops of fresh water that fall as precipitation from clouds
    a product of condensation
    type of:
    binary compound
    chemical compound composed of only two elements
    fluid matter having no fixed shape but a fixed volume
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