The term CHANGER OF LOCKS refers to a person who specializes in replacing locks. PEROXIDE is an 8 letter word that is a chemical compound used as a bleaching agent or disinfectant. DYER is a 4 letter word that refers to someone who dyes fabrics or other materials. HAIRDYE is a 7 letter word that refers to a product used to color hair. All of these words are related to the job description of a CHANGER OF LOCKS, as they all involve changing something in some way.