'chlorine' originates from French 'chlore', ultimately from Greek 'khlōros' meaning 'pale green' or 'greenish-yellow'; the English chemical name was formed with the suffix '-ine' used for halogen elements.

'khlōros' (Greek) → New Latin/modern French 'chlore' → English 'chlorine' (early 19th century); the modern name was popularized in chemical nomenclature after the element's discovery in the late 18th century.

Initially related to the colour 'pale green/greenish-yellow', the term evolved to denote the element (a greenish-yellow gas) and then broadened to substances and compounds containing that element and to its uses (e.g., disinfectant, bleach).