Definition from Wiktionary, the free dictionary
From the French dalle.
- (plural only) The rapids in a deep, narrow stream confined between the rock walls of a canyon or gorge.
- (plural only) A steep-sided part of a stream channel, near the dalles proper, marked by clefts, ravines, or gorges.
- United States Bureau of Mines, Dictionary of Mining, Mineral, and Related Terms (1996).
- plural form of