The Collaborative International Dictionary of English v.0.48:

Trainband \Train"band`\, n.; pl. Trainbands.
   A band or company of an organized military force instituted
   by James I. and dissolved by Charles II.; -- afterwards
   applied to the London militia. [Eng.]
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         He felt that, without some better protection than that
         of the trainbands and Beefeaters, his palace and person
         would hardly be secure.                  --Macaulay.
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         A trainband captain eke was he
         Of famous London town.                   --Cowper.
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