(n) any of five related nonmetallic elements (fluorine or chlorine or bromine or iodine or astatine) that are all monovalent and readily form negative ions
The Collaborative International Dictionary of English (GCIDE) v.0.53 Collaborative International Dictionary (GCIDE)
n. [ Gr. "a`ls, "alo`s, salt + -gen: cf. F. halogène. ] (Chem.) 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 ]
[类金属 / 類金屬, lèi jīn shǔㄌㄟˋ ㄐㄧㄣ ㄕㄨˇ] metalloid (chem.), element with properties intermediate between metals and nonmetals, usually taken to include Boron B 硼, Silicon Si 硅, Germanium Ge 鍺|锗, Arsenic As 砷, Antimony Sb 銻|锑, Tellurium Te 碲, Polonium Po 釙|钋 (sometimes also the halogen Astatine A, See Also: 硼, 硅, 鍺, 锗, 砷, 銻, 锑, 碲, 釙, 钋, 砹