Source : Webster's Revised Unabridged Dictionary (1913)

Immovability \Im*mov"a*bil"i*ty\, n.
   The quality or state of being immovable; fixedness;
   steadfastness; as, immovability of a heavy body; immovability
   of purpose.

Source : WordNet®

immovability
     n : no capable of being moved or rearranged [syn: {immovableness}]
         [ant: {movability}, {movability}]