black spot

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.

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