noun. The act of moving in a swarm, as bees from a hive.

noun. In botany, a method of reproduction observed in some of the Confervaceæ and Desmidiaceæ, in which the granules constituting the green matter become detached from one another and move about in their cells; then the external membrane swells and bursts, and the granules issue forth into the water to become new plants.

noun. The action of a swarm.

noun. A crime where an unsuspecting innocent bystander is attacked by several culprits at once, with no known motive.

verb. Present participle of swarm.