Source : Webster's Revised Unabridged Dictionary (1913)

Bulky \Bulk"y\, a.
   Of great bulk or dimensions; of great size; large; thick;
   massive; as, bulky volumes.

         A bulky digest of the revenue laws.      --Hawthorne.

Source : WordNet®

bulky
     adj : of large size for its weight
     [also: {bulkiest}, {bulkier}]