# ultroneous

> English word · Adjective

## Definitions
1. spontaneous; voluntary

## Etymology
From Latin ultroneus, from ultro (“to the further side, on his part, of one's own accord”). See ultra-.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-09-03.
Canonical page: https://plainspell.com/en/word/ultroneous