spherulin
noun
spher·u·lin
| \ ˈsfir-yə-lən
, ˈsfer-
\
, ˈsfer-
\
Medical Definition of spherulin
: an antigen that is derived from a fungus of the genus Coccidioides (C. immitis) while in its endospore-producing phase and that is used similarly to coccidioidin