The Collaborative International Dictionary of English v.0.48:

Regiment \Reg"i*ment\ (-ment), n. [F. r['e]giment a regiment of
   men, OF. also government, L. regimentum government, fr.
   regere to guide, rule. See Regimen.]
   1. Government; mode of ruling; rule; authority; regimen.
      [Obs.] --Spenser. "Regiment of health." --Bacon.
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            But what are kings, when regiment is gone,
            But perfect shadows in a sunshine day? --Marlowe.
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            The law of nature doth now require of necessity some
            kind of regiment.                     --Hocker.
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   2. A region or district governed. [Obs.] --Spenser.
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   3. (Mil.) A body of men, either horse, foot, or artillery,
      commanded by a colonel, and consisting of a number of
      companies, usually ten.
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   Note: In the British army all the artillery are included in
         one regiment, which (reversing the usual practice) is
         divided into brigades.
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   Regiment of the line (Mil.), a regiment organized for
      general service; -- in distinction from those (as the Life
      Guards) whose duties are usually special. [Eng.]
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