The Collaborative International Dictionary of English v.0.48:

Armory \Ar"mo*ry\, n.; pl. Armories. [OF. armaire, armarie, F.
   armoire, fr. L. armarium place for keeping arms; but confused
   with F. armoiries. See Armorial, Ambry.]
   1. A place where arms and instruments of war are deposited
      for safe keeping.
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   2. Armor; defensive and offensive arms.
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            Celestial armory, shields, helms, and spears.
                                                  --Milton.
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   3. A manufactory of arms, as rifles, muskets, pistols,
      bayonets, swords. [U.S.]
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   4. Ensigns armorial; armorial bearings. --Spenser.
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   5. That branch of heraldry which treats of coat armor.
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            The science of heraldry, or, more justly speaking,
            armory, which is but one branch of heraldry, is,
            without doubt, of very ancient origin. --Cussans.
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WordNet (r) 3.0 (2006):

armory
    n 1: a collection of resources; "he dipped into his intellectual
         armory to find an answer" [syn: armory, armoury,
         inventory]
    2: all the weapons and equipment that a country has [syn:
       arsenal, armory, armoury]
    3: a military structure where arms and ammunition and other
       military equipment are stored and training is given in the
       use of arms [syn: arsenal, armory, armoury]
    4: a place where arms are manufactured [syn: armory,
       armoury, arsenal]