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1. Of considerable importance, size, or worth
   "won by a substantial margin";
   - significant
    
2. Of or relating to the real nature or essential elements of something
   "a substantial argument";
   - substantive
    
3. Providing abundant nourishment
   "ate a substantial breakfast";
   - hearty, satisfying, solid, square
    
4. Of good quality and condition; solidly built
   "several substantial timber buildings";
   - solid, strong
    
5. Having an abundant supply of money or possessions of value
   "a substantial family";
   - affluent, flush, loaded [informal], moneyed, wealthy, minted [informal]
    
6. Having substance or capable of being treated as fact; not imaginary
   "a mere dream, neither substantial nor practical"; "The wind was violent and felt substantial enough to lean against"; "the substantial world";
   - real, material

See also: considerable, essential, material, rich, solidness, sound, substantiality, substantialness, wholesome

Encyclopedia: Substantial