noun
: any of three fungous diseases of the currant:
a. : an angular leaf spot caused by an imperfect fungus ( Cercospora angulata )
b. : an anthracnose characterized by small brownish or black spots and caused by a discomycete ( Pseudopeziza ribis )
c. : a grayish-centered leaf spot caused by an ascomycetous fungus ( Mycosphaerella grossulariae )