# sesquioxide

> English word · Noun

## Definitions
1. Any oxide containing three oxygen atoms for every two atoms of another element.

## Etymology
From sesqui- (“one and a half, a ratio of three to two”) + oxide.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/sesquioxide