hexachlorophene hek suh klaw ruh feen n antibacterial substance that is a water-soluble powder used in antiseptic soaps and toothpaste Usage(s) Among olfactophobic Americans, few chemicals are more commonly used than hexachlorophene. The agency's latest dilemma involves hexachlorophene, the germ killer used in many soaps, deodorants and medicinal cleansers. Before surgery, hair is shampooed repeatedly with a surgical detergent enriched with hexachlorophene to sterilize the scalp.