strath

A wide, flat river valley.

In Scotland, a valley of considerable size, often having a river running through it and giving it its distinctive appellation: as, Strathspey (the valley of the Spey), Strathearn (the valley of the Earn), and Strathmore (the great valley).

A valley of considerable size, through which a river runs; a valley bottom; — often used in composition with the name of the river.

A wide, flat river valley.