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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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Water molecules are made up of two hydrogen atoms and one oxygen atom, giving water its familiar H2O formula.

From Science Daily • May 8, 2026

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

From Barron's • Apr. 16, 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

Over the course of 40-day laboratory experiments involving dehydration, the scientists learned that ferrihydrite loses some absorbed H2O while maintaining its poorly-crystalline structure.

From Salon • Mar. 1, 2025

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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