# indole

> English word · Noun · IPA /ˈɪndəʊl/ · frequency rank #67,528

## Definitions
1. An organic compound, C₈H₇N, found in coal tar, and produced in the gut by the bacterial decomposition of tryptophan; it is an aromatic bicyclic heterocycle having a benzene ring fused with a pyrrole ring; indole and its derivatives occur widely in nature and have many industrial applications.
2. Any of the derivatives of indole.

## Etymology
From indigo + Latin oleum (“oil”); see -ole.

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