cercospora

from The Century Dictionary.

• noun A large genus of hyphomycetous fungi, growing mostly on living leaves, producing dark-colored erect hyphæ, which emerge in clusters from the stomates of the leaf, and bear at their tips elongated septate spores (conidia). Some of the species are injurious to cultivated plants.

from the GNU version of the Collaborative International Dictionary of English.

• noun form genus of imperfect fungi that are leaf parasites with long slender spores.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun form genus of imperfect fungi that are leaf parasites with long slender spores