WordWeb Online

1. Having relatively great weight; heavy
   "a weighty load"; "a weighty package"
    
2. Powerfully persuasive
   "a weighty argument";
   - cogent, telling
    
3. Of great gravity or crucial import; requiring serious thought
   "the weighty matters to be discussed at the peace conference";
   - grave, grievous, heavy
    
4. Weighing heavily on the spirit; causing anxiety or worry
   "weighty problems"
    
5. Excessively fat
   "a weighty man";
   - corpulent, obese, rotund, lardy

Derived forms: weightiest, weightier

See also: fat, heavy, important, of import, persuasive

Antonym: weightless

Encyclopedia: Weighty