%dalles%

n. pl. [ F. dalle a tube, gutter, trough. ] A rapid, esp. one where the channel is narrowed between rock walls. [ Northwestern U. S. & Canada ]

The place below, where the compressed river wound like a silver thread among the flat black rocks, was the far-famed Dalles of the Columbia. F. H. Balch. [ Webster 1913 Suppl. ]