swarm

Short definition from Wiktionary

Noun

1. 1
   A large number of insects, especially when in motion or (for bees) migrating to a new colony.
2. 2
   A mass of people, animals or things in motion or turmoil.
3. 3
   A group of nodes sharing the same torrent in a BitTorrent network.
4. 4
   A number of small earthquakes (or other seismic events) occurring, with no clear cause, in a specific area within a relatively short space of time.

Verb

1. 1
   To move as a swarm.
2. 2
   To teem, or be overrun with insects, people, etc.
3. 3
   To fill a place as a swarm.
4. 4
   To overwhelm as by an opposing army.
5. 5
   To climb by gripping with arms and legs alternately.
6. 6
   To breed multitudes.