The Collaborative International Dictionary of English v.0.48:

Swarm \Swarm\, v. i. [imp. & p. p. Swarmed; p. pr. & vb. n.
   Swarming.]
   1. To collect, and depart from a hive by flight in a body; --
      said of bees; as, bees swarm in warm, clear days in
      summer.
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   2. To appear or collect in a crowd; to throng together; to
      congregate in a multitude. --Chaucer.
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   3. To be crowded; to be thronged with a multitude of beings
      in motion.
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            Every place swarms with soldiers.     --Spenser.
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   4. To abound; to be filled (with). --Atterbury.
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   5. To breed multitudes.
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            Not so thick swarmed once the soil
            Bedropped with blood of Gorgon.       --Milton.
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