Source : Webster's Revised Unabridged Dictionary (1913)

Commonage \Com"mon*age\, n. [Cf. OF. communage.]
   The right of pasturing on a common; the right of using
   anything in common with others.

         The claim of commonage . . . in most of the forests.
                                                  --Burke.

Source : WordNet®

commonage
     n : property held in common