sourdough

noun

1. A type of bread dough leavened with yeast and lactobacilli that produce acids giving a sour taste.

2. slangAn old-timer, especially in Alaska.

3. yukonA permanent resident of the territory. Someone who has lived in the Yukon during all four seasons.

4. A leaven of dough in which fermentation is active; used by pioneers for making bread

5. A settler or prospector (especially in western United States or northwest Canada and Alaska)person