halogen

[hal-uh-juhn, -jen, hey-luh-]

noun

Chemistry.

1. any of the electronegative elements, fluorine, chlorine, iodine, bromine, and astatine, that form binary salts by direct union with metals.

halogen

/ ˈhæləˌdʒɛn, həˈlɒdʒɪnəs /

noun

1. any of the chemical elements fluorine, chlorine, bromine, iodine, and astatine. They are all monovalent and readily form negative ions

halogen

1. 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.

2. See Periodic Table

Other Word Forms

• halogenous adjective
• halogenoid adjective

Word History and Origins

Origin of halogen¹

First recorded in 1835–45; halo- + -gen

Word History and Origins

Origin of halogen¹

C19: from Swedish; see _halo- , _-gen

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