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1. A sudden happening that brings good fortune (as a sudden opportunity to make money)
   "the demand for testing has created a bonanza for those unregulated laboratories where boxes of specimen jars are processed like an assembly line";
   - boom, gold rush, gravy [informal], godsend, manna from heaven, windfall, bunce [Brit, informal]
    
2. An especially rich vein of precious ore

Derived forms: bonanzas

Type of: happening, mineral vein, natural event, occurrence, occurrent, vein

Encyclopedia: Bonanza, North Caribbean Coast Autonomous Region