hydrogen ion

noun

Definition of hydrogen ion

1 : the cation H⁺ of acids consisting of a hydrogen atom whose electron has been transferred to the anion of the acid

2 : hydronium

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Recent Examples of hydrogen ion from the Web

The radio waves are calibrated to target just the less abundant material, in this case hydrogen ions.

— jay bennett, Popular Mechanics, "MIT Achieves Breakthrough in Nuclear Fusion," 28 Aug. 2017
The excited hydrogen ions then slam into the more abundant deuterium ions, and resulting particles fly into the reactor's outer shell, generating heat and electricity.

— jay bennett, Popular Mechanics, "MIT Achieves Breakthrough in Nuclear Fusion," 28 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hydrogen ion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of hydrogen ion

1896

in the meaning defined at sense 1

See Words from the same year

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Medical Dictionary

hydrogen ion

noun

medical Definition of hydrogen ion

1 : the cation H⁺ of acids consisting of a hydrogen atom whose electron has been transferred to the anion of the acid

2 : hydronium

Learn More about hydrogen ion

Britannica.com: Encyclopedia article about hydrogen ion

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