Wiktionary
hydronium
n. (context inorganic chemistry English) the hydrated hydrogen ion, H3O+
Wikipedia
Hydronium
In chemistry, hydronium is the common name for the aqueous cation , the type of oxonium ion produced by protonation of water. It is the positive ion present when an Arrhenius acid is dissolved in water, as Arrhenius acid molecules in solution give up a proton (a positive hydrogen ion, H) to the surrounding water molecules (HO).
Usage examples of "hydronium".
The hydronium ions came in a sudden wave, catching the dividing cells off-guard Buffer systems were mobilized to neutralize some of the initial reactive particles, but there were too many to combat.
As weak acids themselves, they were terribly susceptible to the hydronium ions that swarmed in their midst.