A collective noun is a single word used to denote a group of individuals, animals, or things. The English language is rich with these terms, often possessing surprising or obscure names for assemblies of creatures. Many of these unusual names, especially for insects, originated centuries ago, reflecting a more observational approach to the natural world.
The Collective Nouns for Flies
The most recognized term for a group of flies in flight is a “swarm,” which is the generally accepted collective noun. Flies are also associated with the historical and more archaic collective noun, a “business” of flies. This unusual term is thought to originate from the constant, erratic movement of the insects as they cluster together. Another descriptive and less common name is a “cloud” of flies, which focuses on the visual density of the grouping. When aquatic insects, such as midges, emerge from the water simultaneously, the resulting group is sometimes referred to as a “hatch” of flies.
Understanding Swarming Behavior
The behavior that creates a “swarm” or a “cloud” is often driven by the biological necessity of mating, particularly among true flies (Diptera). Males of species like midges aggregate in the air to form conspicuous aerial clusters, a phenomenon known as lek mating. This dense gathering increases the encounter rate with females, who typically enter the swarm briefly to select a mate. These mating swarms frequently form above a distinctive visual marker, such as a bush, a fence post, or a person’s head. Flies also aggregate for feeding purposes, clustering tightly around a rich food source like carrion or decaying matter, or to seek warmth or moisture.
Collective Nouns for Other Common Insects
Collective nouns extend beyond flies to cover other common insects, reflecting diverse behaviors and appearances. A group of gnats, small flying insects related to midges, is often called a “cloud,” a “horde,” or a “rabble,” emphasizing their density.
Ants, which are social insects, are typically referred to as a “colony,” describing their structured community life within a nest. When moving in a large, organized file, they can be described as an “army” of ants.
The migratory movement of butterflies has inspired the term “kaleidoscope,” fitting for a mass of their colorful wings. The collective noun for bees leaving a hive to establish a new one is a “swarm,” but a group of caterpillars is uniquely called an “army.”