What is the meaning of Indole?

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.

Any of the derivatives of indole.

guileless

indole

nature, disposition, character

ablative singular of indolēs

Source: wiktionary.org