# fresnel

> English word · Noun · frequency rank #58,037

## Definitions
1. A unit of frequency equal to 10¹² hertz, or one terahertz.
2. A Fresnel lens or a light feature using such a lens

## Etymology
For Augustin-Jean Fresnel, French physicist.

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