The Collaborative International Dictionary of English v.0.48:

Brigade \Bri*gade"\, n. [F. brigade, fr. It. brigata troop,
   crew, brigade, originally, a contending troop, fr. briga
   trouble, quarrel. See Brigand.]
   1. (Mil.) A body of troops, whether cavalry, artillery,
      infantry, or mixed, consisting of two or more regiments,
      under the command of a brigadier general.
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   Note: Two or more brigades constitute a division, commanded
         by a major general; two or more divisions constitute an
         army corps, or corps d'arm['e]e. [U.S.]
         [1913 Webster]

   2. Any body of persons organized for acting or marching
      together under authority; as, a fire brigade.
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   Brigade inspector, an officer whose duty is to inspect
      troops in companies before they are mustered into service.


   Brigade major, an officer who may be attached to a brigade
      to assist the brigadier in his duties.
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