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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

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

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

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

Later, for no special reason, the fashion became to render the number as subscript: H2O.

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