A group of minnows is called a fleet, a naval-sounding term for one of the smallest fish in freshwater ecosystems. Minnows are a broad category covering many small freshwater species, and they’re a foundational food source for larger fish, birds, and mammals throughout rivers, streams, and lakes.
“Fleet” captures the way minnows move: in fast, tightly coordinated schools that dart and turn almost instantaneously, a defense mechanism that makes it harder for a predator to lock onto any single fish. Unlike a naval fleet, though, there’s no command structure involved, the tight formation is a purely instinctive response to threat.
Bonus fact: minnows are often used as a biological indicator species by researchers, since they’re highly sensitive to water pollution and oxygen levels, a thriving population of minnows is a strong sign of a healthy waterway.
Minnows are also occasionally described using other general fish terms like a shoal or a swarm, but “fleet” remains the most commonly cited term specific to this fish.
Related: Collective Nouns for Fish