The Collaborative International Dictionary of English v.0.48:

Legion \Le"gion\ (l[=e]"j[u^]n), n. [OE. legioun, OF. legion, F.
   l['e]gion, fr. L. legio, fr. legere to gather, collect. See
   Legend.]
   1. (Rom. Antiq.) A body of foot soldiers and cavalry
      consisting of different numbers at different periods, --
      from about four thousand to about six thousand men, -- the
      cavalry being about one tenth.
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   2. A military force; an army; military bands.
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   3. A great number; a multitude.
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            Where one sin has entered, legions will force their
            way through the same breach.          --Rogers.
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   4. (Taxonomy) A group of orders inferior to a class.
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   Legion of honor, an order instituted by the French
      government in 1802, when Bonaparte was First Consul, as a
      reward for merit, both civil and military.
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