1. plural of firth; narrow inlets of the sea between cliffs or steep banks
Usage: chiefly Scottish

Examples

• The Scottish Highlands are famous for their dramatic firths cutting into the coastline.
• Several firths along the coast provide excellent natural harbors.
• The Firth of Forth and the Firth of Clyde are well-known Scottish waterways.
• Small fishing villages dot the shores of these ancient firths.
• The tide rushes in and out of the narrow firths twice daily.
• Many firths were carved by glacial action thousands of years ago.