# indicatrix

> English word · Noun

## Definitions
1. An ellipsoid whose three axes represent the refractive indices of an anisotropic crystal for light following different directions with respect to the crystal axes

## Etymology
Learned borrowing from Latin indicātrīx. By surface analysis, indicate + -trix.

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