any of the chemical elements fluorine, chlorine, bromine, iodine, and astatine. They are all monovalent and readily form negative ions
WordReference Random House Learner's Dictionary of American English © 2026
hal•o•gen /ˈhælədʒən, -ˌdʒɛn, ˈheɪlə-/USA pronunciation
n.
WordReference Random House Unabridged Dictionary of American English © 2026- Chemistryany of various elements, as fluorine, chlorine, iodine, and bromine, that have properties in common: [uncountable]the use of halogen in lamps.[countable]halogens as health hazards.
hal•o•gen
(hal′ə jən, -jen′, hā′lə-),USA pronunciation n. [Chem.]
ha•log•e•nous
(ha loj′ə nəs),USA pronunciation adj.
- Chemistryany of the electronegative elements, fluorine, chlorine, iodine, bromine, and astatine, that form binary salts by direct union with metals.
- 1835–45; halo- + -gen
Collins Concise English Dictionary © HarperCollins Publishers::
'halogen' also found in these entries (note: many are not synonyms or translations):
-ine
- Grignard reagent
- Hal
- alkyl halide
- astatine
- bromine
- chlorine
- family
- fluorine
- halide
- halo
- halo-
- halogen lamp
- halogenate
- haloid
- halon
- iodine
- quartz-iodine lamp
- silver halide
- subhalide
- tungsten lamp