hydronium
/haɪˈdɹoʊ.ni.əm/noun
hydronium is a noun meaning “The hydrated hydrogen ion, H₃O⁺” (English Wiktionary, September 2026). It is spelled H-Y-D-R-O-N-I-U-M and has 4 syllables, and it appears about once in every 36 million words in written English (wordfreq, 2021 data). The plural of hydronium is hydroniums.
What does hydronium mean?
noun
- 1
The hydrated hydrogen ion, H₃O⁺.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
How do you pronounce hydronium?
- UK /haɪˈdɹəʊ.ni.əm/
- US /haɪˈdɹoʊ.ni.əm/
Hydronium has 4 syllables (counted from the pronunciation).
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Recordings: LL-Q1860_(eng)-Tesco250-hydronium.wav, Wikimedia Commons (author and licence on each file's page).
Forms of hydronium
- hydroniums plural
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
How common is hydronium?
Hydronium appears about once in every 36 million words in written English, the 184,844th most frequent word form in the list.
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
Hydronium in Spanish, French, German and Portuguese
In the sense H3O+:
| Language | Words |
|---|---|
| German | Hydronium |
| Spanish | hidronio |
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Translations are Wiktionary's, by sense; a linked word has its own PlainSpell page.
Where does hydronium come from?
From hydro- + onium.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).