noun
bee ball; swarm cluster
Beekeeping term for a dense cluster of honey bees, often formed during swarming or as a defensive behavior against hornets.
ミツバチが蜂球を作ってスズメバチを蒸し殺す。
Honey bees form a bee ball and heat-kill the hornet.
養蜂家は蜂球を巣箱に移した。
The beekeeper moved the swarm cluster into a hive.