# Tissot's indicatrix

> English word · Noun

## Definitions
1. A mathematical contrivance used to characterize local distortions due to map projection. It is the geometry that results from projecting a circle of infinitesimal radius from a curved geometric model, such as a globe, onto a map.

## Etymology
Developed by French mathematician Nicolas Auguste Tissot in the 19th century.

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