Word Type

Noun

The word "onium" can be used as a noun.

Word Relationships

Derived Terms

hydronium leptonium

Etymologically Related To

ammonium

Context

chemistry physics

Broader Terms (Hypernyms)

cation ion

Related Terms

addition ammonium antiparticle arsonium bismuthonium bromonium cation chalcogen chloronium derivative element fluoronium halogen hydride iodonium muononium nitrogen organic oxonium particle phosphonium positronium proton selenonium stibonium sulfonium tauonium telluronium toponium

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.