black spot

[blak spot for 1; blak spot for 2] /ˈblæk ˈspɒt for 1; ˈblæk ˌspɒt for 2/
noun
1.
Plant Pathology. a disease of plants, characterized by black spots on the fruit and foliage, twig lesions, defoliation, and rotting, caused by any of several fungi, as Diplocarpon rosae, or bacteria.
2.
British.
  1. a hazardous place in a road where accidents frequently occur.
  2. a dangerous area or place.
Also, blackspot.
Origin
1885-90
British Dictionary definitions for blackspot

black spot

noun
1.
a place on a road where accidents frequently occur
2.
any dangerous or difficult place
3.
a disease of roses, Diplocarpon rosae, that causes circular black blotches on the leaves
Encyclopedia Article for blackspot

black spot

common disease of several plants that is caused by species of Pseudomonas bacteria or by many fungus species in the genera Asterina, Asterinella, Asteroma, Diplotheca, Glomerella, Gnomonia, Microthyriella, Placosphaeria, and Stigmea. Infections occur during damp periods and appear as round to irregular black leaf spots, sometimes on petioles, stems, and flower parts

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