free electron

American

noun

Physics.

an electron that is not attached to an atom or molecule and is free to respond to outside forces.

free electron British

noun

any electron that is not attached to an ion, atom, or molecule and is free to move under the influence of an applied electric or magnetic field

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of free electron

First recorded in 1905–10

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The microscope has two key components: a soft X-ray free electron laser; and highly precise Wolter mirrors, a type of mirror widely used in X-ray telescopes for observing space.

From Science Daily • May 24, 2024

In this way, the researchers simulate a complex state similar to the one produced in the solid state by a free electron.

From Science Daily • Oct. 26, 2023

In a free electron laser, a linear accelerator, or linac, shoots a beam of high-energy electrons into a string of complex magnets called undulators.

From Science Magazine • Sep. 18, 2023

Electrons are accelerated before entering an X-ray free electron laser.

From Nature • Jan. 29, 2014

Charley danced and flicked around the cabin like a free electron with a careless disregard for traffic regulations and public safety.

From Master of the Moondog by Mullen, Stanley

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023