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. American History, Usually Disparaging.,  Also Blue Light 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

“Melatonin is what makes you sleepy. The effect of the blue light is that it makes you more awake and alert.”

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“When our eye gets that blue light, enough of it, then it suppresses the body’s melatonin production,” says Jonathan Clark, chief executive of Innerscene, a San Francisco-based lighting-equipment manufacturer.

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“We always say that red pigments absorb blue light,” the authors tell us, which is the reason red creatures often appear black in the deep sea.

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And yet atollas gain their reddish coloration from pigments called porphyrins, which don’t absorb blue light all that well and which, if exposed to bright light, emit toxins.

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As she neared the window, she combed her fingers through the cool blue light and watched her hand turn into a ghostly puppet.

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