n.
Pronunciation: ' sau ̇ (- ə )r- ˌ d ō , 1 is also - ' d ō
Function: noun
Date: 14th century
1 : a leaven consisting of dough in which fermentation is active
2 [from the use of sourdough for making bread in prospectors' camps] : a veteran inhabitant and especially an old-time prospector of Alaska or northwestern Canada