halogen
Americannoun
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halogens
plural
noun
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Any of a group of five nonmetallic elements with similar properties. The halogens are fluorine, chlorine, bromine, iodine, and astatine. Because they are missing an electron from their outermost shell, they react readily with most metals to form salts.
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See Periodic Table
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Explanation
A halogen is a chemical element that forms a salt when it reacts with metal. Halogen lamps are illuminated by bulbs that contain a halogen and an inert gas. There are five halogens in the periodic table of chemical elements: fluorine, chlorine, bromine, iodine, and astatine. The halogens are all highly reactive, which means they're quick to form bonds with other elements. What they often end up becoming is some kind of salt, including common table salt. In fact, the literal translation of halogen is "salt-producer," from Greek roots hals, "salt," and gen, "giving birth to."
Vocabulary lists containing halogen
Chemistry - High School
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Structure and Properties of Matter - High School
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Example Sentences
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He did a more-than-competent job—he was Rossini after all—but the result always reminds me of shining a halogen light into a place of hallowed dim.
From The Wall Street Journal ● May 15, 2026
Another problem is the illegal retrofitting of LED bulbs, especially when fitted into units designed for halogen.
From BBC ● Feb. 18, 2026
"The resulting datasets are producing an improved understanding of the interactions between sea-spray aerosols, surface-coupled clouds, oil field emissions and multiphase halogen chemistry in the new Arctic."
From Science Daily ● Dec. 29, 2025
The beam is whiter, more focused and brighter than the more diffuse light from halogen lamps fitted in older cars.
From BBC ● Oct. 27, 2025
As the broiling sun set, a different kind of American landscape lit up: The halogen floodlights from the truck stop could be seen for miles.
From "Geeks: How Two Lost Boys Rode the Internet Out of Idaho" by Jon Katz
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The researchers now want to investigate ways to confine the molten salts, potentially using halogens or carbon-based materials, which could make the salts easier to separate and process while improving their stability.
From Science Daily ● Sep. 21, 2026
Firstly, they are two to three times as bright as traditional halogens, and their "colour temperature" is bluer and whiter, which mimics natural daylight.
From BBC ● Feb. 18, 2026
A team from France and Germany has now studied the rapid decay of molecules containing halogens.
From Science Daily ● Dec. 2, 2024
The metals of group 13 all react directly with nonmetals such as sulfur, phosphorus, and the halogens, forming binary compounds.
From Textbooks ● Feb. 14, 2019
Thus chlorine and the rest of the halogens, the atoms of which combine with one atom of hydrogen, are called univalent, oxygen a bivalent element, and so on.—ED.
From The New Physics and Its Evolution by Lucien Poincaré
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