# Lenard ray

> English word · Noun

## Definitions
1. One of the rays that emanate from the outer surface of a plate composed of any material permeable by cathode rays, such as aluminium, which forms a portion of a wall of a vacuum tube, or which is mounted within the tube and exposed to radiation from the cathode.

## Etymology
Named after the German physicist Philipp Lenard, who first described them.

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