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

Competition for light, water and nutrients immediately sets in.

From Los Angeles Times • Mar. 13, 2026

Photosynthesis is the central process by which plants build up biomass using light, water and the carbon dioxide from the air.

From Science Daily • Apr. 8, 2024

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

Municipalities in the United States should own and operate plants for supplying light, water, and surface transportation.

From Carnegie Library of Pittsburgh Debate Index Second Edition by Carnegie Library of Pittsburgh