light water

American  

noun

1. ordinary water, as opposed to heavy water; water containing the normal proportion of deuterium oxide.

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light water British  

noun

1. a name for water (H 2 O), as distinct from heavy water

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light water Scientific  

1. Ordinary water, H ₂ O.

2. Compare heavy water

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Etymology

Origin of light water

First recorded in 1930–35

Example Sentences

See Examples For:

light water

The new pools are intended to handle year-round use, incorporating electric pool heaters, salt water and UV light water treatment.

From Los Angeles Times ● Jul. 2, 2025

"Understanding where, and how much, of that fresh and light water enters the Atlantic Ocean is critical to predict how the circulation may evolve under climate change," Duyck says.

From Science Daily ● Oct. 24, 2023

It asserts that with its approach, nuclear fuel is used “up to a hundred times better” than in traditional light water reactors.

From Seattle Times ● Sep. 13, 2023

But millions have been left without light, water or heat as winter sets in.

From BBC ● Nov. 25, 2022

The air is light, water boils at a low temperature, and our lungs and muscles seem inadequate to perform their usual functions.

From Under the Maples by Burroughs, John