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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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That’s the challenge—and opportunity—facing industrial stocks that specialize in H2O.

From Barron's • Apr. 16, 2026

"If we're going to send humans to Mars, you need H2O and not just for drinking, but for propellant and all manner of applications," Luzzi said.

From Science Daily • Dec. 27, 2025

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

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

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