Roost

A strong current or furious tide betwixt island groups.

“This lofty promontory is constantly exposed to the current of a strong and furious tide, which, setting in betwixt the Orkney and Zetland islands, and running with force only inferior to that of the Pentland Frith, … is called the. Roost of Sumburgh [from the headland].”—Sir Walter Scott: The Pirate, chap. i.