Word Study
halogen
CIDE DICTIONARY
halogen, n. [Gr. "a`ls, "alo`s, salt + -gen: cf. F. halogène.].
An electro-negative element or radical, which, by combination with a metal, forms a haloid salt; especially, chlorine, fluorine, bromine, and iodine; sometimes, also cyanogen. See Chlorine family , under Chlorine. [1913 Webster]
OXFORD DICTIONARY
halogen, n. Chem. any of the group of non-metallic elements: fluorine, chlorine, bromine, iodine, and astatine, which form halides (e.g. sodium chloride) by simple union with a metal.
Derivative
halogenic adj.
Etymology
Gk hals halos salt
For further exploring for "halogen" in Webster Dictionary Online