The Collaborative International Dictionary of English v.0.48:

Armament \Ar"ma*ment\, n. [L. armamenta, pl., utensils, esp. the
   tackle of a ship, fr. armare to arm: cf. LL. armamentum, F.
   armement.]
   1. A body of forces equipped for war; -- used of a land or
      naval force. "The whole united armament of Greece."
      --Glover.
      [1913 Webster]

   2. (Mil. & Nav.) All the cannon and small arms collectively,
      with their equipments, belonging to a ship or a
      fortification.
      [1913 Webster]

   3. Any equipment for resistance.
      [1913 Webster]

WordNet (r) 3.0 (2006):

armament
    n 1: weaponry used by military or naval force
    2: the act of equiping with weapons in preparation for war [syn:
       arming, armament, equipping] [ant: disarmament,
       disarming]

Moby Thesaurus II by Grady Ward, 1.0:

84 Moby Thesaurus words for "armament":
   A-weapons, accouterment, accouterments, aegis, apparatus,
   appliances, appointments, appurtenances, armor, arms,
   biological weapons, catering, chandlery, conveniences,
   conventional weapons, deadly weapons, duffel, endowment, equipage,
   equipment, facilities, facility, finding, fitting out, fittings,
   fixtures, furnishing, furnishings, furnishment, furniture, gear,
   guard, impedimenta, installations, instruments of destruction,
   investment, kit, logistics, machinery, materiel, missilery,
   munition, munitions, musketry, nuclear weapons, ordnance, outfit,
   outfitting, paraphernalia, plant, plumbing, preparation,
   procurement, protection, providing, provision, provisioning,
   purveyance, reinforcement, replenishment, resupply, retailing, rig,
   rigging, safeguard, security, selling, shield, side arms,
   small arms, stock-in-trade, subsidization, subsidy, subvention,
   supply, supplying, tackle, thermonuclear weapons, things, utensils,
   victualing, ward, weaponry, weapons