Definition of heavy water in English:

heavy water


  • [mass noun] Water in which the hydrogen in the molecules is partly or wholly replaced by the isotope deuterium, used especially as a moderator in nuclear reactors.

    • ‘Heavy-water nuclear facilities react natural, un-enriched uranium oxide as fuel, hence they need heavy water as a more efficient moderator.’
    • ‘Deuterium, a heavy and stable isotope of hydrogen, binds to oxygen to form deuterium oxide, commonly known as heavy water.’
    • ‘It will be 10 years in the making and, in its 20-year operating life, researchers will experiment with a kind of slow hydrogen bomb in the hope of extracting vast amounts of clean energy from tiny amounts of heavy water.’
    • ‘We even found that feeding cells heavy water gave them a 27-minute cycle of growth and rest, so that old piece of information served to confirm our theory.’
    • ‘Because of their heavier weight, heavy water molecules evaporate less readily than light water molecules.’
    • ‘Indeed, we talk of heavy water as water, and there seems no non-stipulative reason not to do so.’
    • ‘Both natural and heavy water were used as solvents.’
    • ‘Included are uranium in raw, depleted and enriched forms, heavy water, and equipment for the production of heavy water.’
    • ‘The heavily guarded factory produced heavy water, one of the materials used to control atomic fission.’
    • ‘The most common moderators are substances of low atomic weight such as heavy water (deuterium oxide) or graphite.’
    • ‘Dean found the effect with either tap water or distilled water and also in a single test with heavy water, and he noted that it had first been observed in a saline solution.’
    • ‘In another experiment, bean plants grown from seed given increasing fractions of heavy water showed stunted growth compared with control plants given normal water.’
    • ‘Employees were found ‘not following proper procedures’ when dealing with the radioactive heavy water moderator.’
    • ‘In heavy water the hydrogen bonds are slightly stronger, and this changes the properties of the liquid sufficiently to disrupt the lubricating effect water has on biochemical processes.’
    • ‘Because heavy water is very efficient as a coolant and moderator in nuclear power plants, greater quantities were wanted than occur naturally.’
    • ‘He expects that heavy water restrictions are in the pipeline if the desalination plant is not developed.’
    • ‘Why do you need heavy water to develop a commercial nuclear reactor?’


heavy water