WordWeb Online

1. Imposing in size or bulk or solidity
   "massive oak doors"; "Moore's massive sculptures"
   - monolithic, monumental
    
2. Being the same substance throughout
   "massive silver"
    
3. Imposing in scale or scope or degree or power
   "massive retaliatory power"; "a massive increase in oil prices"; "massive changes"
    
4. Consisting of great mass; containing a great quantity of matter
   "Earth is the most massive of the terrestrial planets"

See also: big, heavy, large, massively, massiveness, solid

Encyclopedia: Massive