blue light

[ bloo lahyt ]

noun

1. a band of the visible light spectrum that has a shorter wavelength and produces higher energy than other colors of light: occurring in sunlight and emitted by electronic devices that use LED technology.
2. Also Blue Light. American History, Usually Disparaging. a member of a faction of the American Federalist party considered disloyal for opposing the War of 1812: so called from the claim that they flashed blue light signals to alert the British to the presence of blockade runners.

Word History and Origins

Origin of blue light¹

First recorded in 1810–15

Example Sentences

That includes after the game donning a pair of rose-tinted sunglasses that block blue light.

From Los Angeles Times

A hole was cut to let the beam of light shine through and a mirror was placed at the base to split the beam into smoky rays of blue light.

From Los Angeles Times

I had traveled to Montana to observe and participate in the American democratic process, the way most Americans engage with American democracy—not in union halls or public forums, but on the receiving end of a one-way fire hose of paid propaganda and professional manipulation, rendered in 30-second bursts of flickering blue light, largely in isolation, via television.

From Slate

And for the next two nights, the Coliseum’s peristyle will be illuminated in blue light.

From Los Angeles Times

For more than a week straight, photographers, scientists and adventure seekers alike have captured dazzling images of an electric blue light emitting from Southern California’s waves at night.

From Los Angeles Times