- a limited, often circular, discolored, diseased area on a leaf, usually including a central region of necrosis.
- any disease so characterized.
Origin of leaf spot
First recorded in 1900–05
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for leaf spot
Mr. Durand: What is the best spray for leaf-spot and rust in strawberries?
Black walnuts suffer from leaf-spot, blight, or canker, especially in seasons when the trees have been weakened by drought.
Mosaic disease, Frog-eye or Leaf-spot are probably bacterial diseases.Tobacco Leaves
W. A. Brennan
Thus we have "shot-hole fungus," "leaf-spot" and "leaf-blight" as effects of these diseases.The Cherries of New York
U. P. Hedrick
Carnations are subject to several diseases, the worst being the “rust” (Uromyces Caryophilinus), “leaf-spot” and maggot.
- any of various plant diseases, usually caused by fungi: characterized by dark lesions on the leaves
- Any of various plant diseases resulting in well-defined necrotic areas on the leaves.
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