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Showing results for H2O. Search instead for H3O.
Synonyms

H2O

Cultural  

  1. The chemical symbol (see also symbol) for water. Each molecule of water contains two atoms of hydrogen (H) joined to a single atom of oxygen (O).

Example Sentences

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Continued heating produces ferric hydroxysulfate, where OH replaces H2O in the mineral structure.

From Science Daily • Mar. 10, 2026

H2O is the stuff of life, but for several decades, water producers and sommeliers have been working to make it something more: the stuff of taste.

From The Wall Street Journal • Oct. 20, 2025

He has denied the existence of Covid, questioned the moon landing and claims that water is something other than H2O.

From BBC • Dec. 10, 2024

The business of boosting one’s H2O is projected to reach $3.26 billion by 2031.

From Los Angeles Times • Jul. 22, 2024

To indicate the number of atoms in a molecule, Berzelius employed a superscript notation, as in H2O.

From "A Short History of Nearly Everything" by Bill Bryson

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.