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1. Of the highest quality, skill, etc.; very good or impressive
   - ace [informal], A-one [informal], crack [informal], first-rate, super, tiptop, topnotch [informal], top-notch [informal], tops [informal], A1 [informal], excellent, first-class, fantabulous [informal], splendid, ripping [Brit, informal], mean [informal], beezer [UK, archaic], lush [Brit, informal], stellar [informal], awesome [informal], outstanding, top-drawer
    
2. Of surpassing excellence
   "a brilliant performance";
   - superb, magnificent
    
3. Having or marked by unusual and impressive intelligence
   "a brilliant mind";
   - brainy [informal], smart as a whip [informal]
    
4. Characterized by grandeur
   "the brilliant court life at Versailles";
   - glorious, magnificent, splendid, majestic
    
5. Having strong or striking colour
   "brilliant tapestries";
   - bright, vivid
    
6. Full of light; shining intensely
   "a brilliant star"; "brilliant chandeliers"
    
7. Clear and sharp and ringing
   "the brilliant sound of the trumpets";
   - bright

See also: ace [informal], amazeballs [informal], awesomesauce [informal], beaut [Austral, NZ, informal], blinding [Brit, slang], bright, brill [Brit, informal], clever-clever, colorful [US], colourful [Brit, Cdn], crucial [slang], cushty [Brit, informal], def [slang], fab [Brit, informal], impressive, intelligent, legit [US, slang], lit [US, slang], magic [Brit, slang], nang [Brit, slang], phat [slang], rad [N. Amer, slang], radical [N. Amer, slang], reverberant, righteous [US, slang], sick [N. Amer, slang], smokin' [slang], smoking [slang], socko [N. Amer, informal], stonking [Brit, informal], storming [Brit, informal], super [informal], super-duper [informal], superior, wicked [slang]

Encyclopedia: Brilliant, Al