coccidioidin

coc·cid·i·oi·din

noun \-ˈȯid-^ən, -ˈȯi-ˌdin\

Definition of COCCIDIOIDIN

: an antigen derived from a fungus of the genus Coccidioides (C. immitis) while in its mycelial phase and used to detect skin sensitivity to and, by inference, infection with this organism—compare spherulin