erythrasma

noun
er·​y·​thras·​ma | \ ˌer-ə-ˈthraz-mə How to pronounce erythrasma (audio) \

Medical Definition of erythrasma

: a chronic contagious dermatitis that affects warm moist areas of the body (as the armpit and groin) and is caused by a bacterium of the genus Corynebacterium (C. minutissimum)