myeloperoxidase

noun

my·​e·​lo·​per·​ox·​i·​dase ˌmī-ə-lō-pə-ˈräk-sə-ˌdās, -ˌdāz 

: a green peroxidase of phagocytic cells (as neutrophils and monocytes) that is held to assist in bactericidal activity by catalyzing the oxidation of ionic halogen to free halogen