[eye.spot] n (1877) 1 a: a simple visual organ of pigment or pigmented cells covering a sensory termination: ocellus b: a small pigmented body of various unicellular algae
2: a spot of color
3: any of several fungal diseases of plants characterized by yellowish oval lesions on the leaves and stem; esp: a disease of various grasses (as sugarcane) caused by a fungus (Helminthosporium sacchari)