subject to a process or treatment, with the aim of readying for some purpose, improving, or remedying a condition

disinfection of water by the addition of small amounts of chlorine or a chlorine compound

the addition or substitution of chlorine in organic compounds

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)