cluster fly

noun

1. a black fly, Pollenia rudis, slightly larger than the housefly, commonly found hibernating in large numbers in homes in the fall.

cluster fly

noun

1. a dipterous fly, Pollenia rudis, that tends to gather in large numbers in attics in the autumn: family Calliphoridae. The larvae are parasitic in earthworms

Example Sentences

Another frequent visitant of houses, particularly in the spring and fall, is the cluster fly.

From Project Gutenberg