# tropylium

> English word · Noun

## Definitions
1. The delocalized carbenium ion cycloheptatrienylium, C₇H₇⁺, derived from cycloheptatriene, or any of its derivatives.

## Etymology
From tropine + -yl + -ium.

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