Pentland Firth [pent-luh nd] noun
- a strait between N Scotland and the Orkney Islands, linking the North Sea to the Atlantic Ocean: noted for its rough sea conditions. 14 miles (23 km) long.
British Dictionary definitions for pentland firth Pentland Firth noun
- a channel between the mainland of N Scotland and the Orkney Islands: notorious for rough seas. Length: 32 km (20 miles). Width: up to 13 km (8 miles)