a greenish-yellow, poisonous, gaseous chemical element, one of the halogens, having a disagreeable odor and obtained by electrolysis of certain chlorides: it is used as a bleaching agent, in water purification, in various industrial processes, etc.: symbol, Cl; at. no. 17
Origin of chlorine; from Classical Greek chl?ros, pale green (; from Indo-European an unverified form ghl?-, variant, variety of base an unverified form ghel-: see yellow) + -ine: so named (1810), from its color, by Sir Humphry Davy, who proved it to be an element
A highly irritating, greenish-yellow halogen element, existing as a diatomic gas, Cl2, and capable of combining with nearly all other elements, produced principally by electrolysis of sodium chloride and used widely to purify water, as a disinfectant and bleaching agent, and in the manufacture of many important compounds including chlorates, sodium hypochlorite, and chloroform. Atomic number 17; atomic weight 35.453; freezing point −100.5°C; boiling point −34.04°C; specific gravity 1.56 (−33.6°C); valence 1, 3, 5, 7. See Periodic Table.
- A toxic, green, gaseous chemical element (symbol Cl) with an atomic number of 17.
Coined by Sir Humphry Davy from Ancient Greek χλωρός (khlōros, “pale green”)