Source : Webster's Revised Unabridged Dictionary (1913)

Instrumentality \In`stru*men*tal"i*ty\, n.; pl.
   {Instrumentalities}.
   The quality or condition of being instrumental; that which is
   instrumental; anything used as a means; medium; agency.

         The instrumentality of faith in justification. --Bp.
                                                  Burnet.

         The discovery of gunpowder developed the science of
         attack and defense in a new instrumentality. --J. H.
                                                  Newman.

Source : WordNet®

instrumentality
     n 1: a subsidiary organ of government created for a special
          purpose; "are the judicial instrumentalities of local
          governments adequate?"; "he studied the French
          instrumentalities for law enforcement"
     2: the quality of being instrumental for some purpose
     3: an artifact (or system of artifacts) that is instrumental in
        accomplishing some end [syn: {instrumentation}]