1. Bread made with fermented dough starter that gives it a distinctively tangy taste
   "The bakery was known for its tangy sourdough bread";
   - sour bread [US], sourdough bread
    
2. A bread dough fermented with wild yeast and lactobacilli bacteria
   "The baker maintained her sourdough starter for years"
    
3. [N. Amer] A settler or prospector (especially in western United States or northwest Canada and Alaska)
   "The old sourdough regaled us with tales of the Klondike Gold Rush"

Derived forms: sourdoughs

Type of: bread, breadstuff, colonist, leaven, leavening, prospector, settler, staff of life

Encyclopedia: Sourdough, Montana