Phrase guide

hydrogen ion

noun · 4 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

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1

noun

Meaning 1

Used other than figuratively or idiomatically: see hydrogen, ion.: H− or H+

Definition source: English Wiktionary via Wiktextract

Topics: chemistry, natural-sciences, physical-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

a proton combined with one or more water molecules; usually written H3O+ and called the hydronium ion though is best considered as H9O4+ but is often written H+_((aq)) for simplicity

Definition source: English Wiktionary via Wiktextract

Topics: chemistry, natural-sciences, physical-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

noun

Meaning 3

a bare hydrogen nucleus; a proton, deuteron or triton

Definition source: English Wiktionary via Wiktextract

Topics: chemistry, natural-sciences, physical-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

4

noun

Meaning 4

a positively charged atom of hydrogen; that is to say, a normal hydrogen atomic nucleus

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: cation, proton

History

Etymology

No etymology was provided for this word.