Library / English Dictionary

HALOGEN

Pronunciation (US):

(GB):

 I. (noun) 

Sense 1

Meaning:

Any of five related nonmetallic elements (fluorine or chlorine or bromine or iodine or astatine) that are all monovalent and readily form negative ions

Classified under:

Nouns denoting substances

Hypernyms ("halogen" is a kind of...):

group; grouping (any number of entities (members) considered as a unit)

Hyponyms (each of the following is a kind of "halogen"):

astatine; At; atomic number 85 (a highly unstable radioactive element (the heaviest of the halogen series); a decay product of uranium and thorium)

atomic number 35; Br; bromine (a nonmetallic heavy volatile corrosive dark brown liquid element belonging to the halogens; found in sea water)

atomic number 17; chlorine; Cl (a common nonmetallic element belonging to the halogens; best known as a heavy yellow irritating toxic gas; used to purify water and as a bleaching agent and disinfectant; occurs naturally only as a salt (as in sea water))

atomic number 9; F; fluorine (a nonmetallic univalent element belonging to the halogens; usually a yellow irritating toxic flammable gas; a powerful oxidizing agent; recovered from fluorite or cryolite or fluorapatite)

atomic number 53; I; iodin; iodine (a nonmetallic element belonging to the halogens; used especially in medicine and photography and in dyes; occurs naturally only in combination in small quantities (as in sea water or rocks))

Credits

 Context examples: 

A compound that can increase human cancer risk and consists of hydrogen and carbon atoms arranged in a symmetrical 6-carbon ring structure with single and double bonds alternating around the ring (benzene ring) and in which at least one of the hydrogen atoms is substituted for a halogen (chlorine, bromine, fluorine) atom.

(Carcinogenic Halogenated Aromatic Hydrocarbon, NCI Thesaurus)