Muniment /(?)/

Mu·ni·ment

Muniment

n.
  1. The act of supporting or defending. [Obs.]
  2. That which supports or defends; stronghold; place or means of defense; munition; assistance.
  3. A record; the evidences or writings whereby a man is enabled to defend the title to his estate; title deeds and papers. (Law)

Phrases & Compounds
Muniment room
that room in a cathedral, castle, or other public building, which is used for keeping the records, charters, seals, deeds, and the like.