The Collaborative International Dictionary of English v.0.48:

Muniment \Mu"ni*ment\, n. [L. munimentum, fr. munire to fortify.
   See Munition.]
   1. The act of supporting or defending. [Obs.]
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   2. That which supports or defends; stronghold; place or means
      of defense; munition; assistance. "Other muniments and
      petty helps." --Shak.
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   3. (Law) A record; the evidences or writings whereby a man is
      enabled to defend the title to his estate; title deeds and
      papers. --Blount.
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   Muniment room or Muniment house, that room in a
      cathedral, castle, or other public building, which is used
      for keeping the records, charters, seals, deeds, and the
      like. --Gwilt.
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