Geographic Landforms

Key Terms and DefinitionsFor

Washington State History-7

Mountain

• A landform that rises at least 1,000 feet above the surrounding area.

Valley

• An elongated depression, usually with an outlet, between bluffs, hills or mountains.

Basin

• A depression like a bowl that is a circular or oval shape in the ground.

Plateau

• An elevated plain or flat-topped region of considerable extent.

Peninsula

• An elongated portion of land nearly surrounded by water and connected to a larger body of land.

Harbor

• A water area nearly surrounded by land or seawalls forming a safe anchorage for ships.

Bay

• A body of water that is partly enclosed by land and is smaller than a gulf.

Coastline

• The line that forms the boundary between land and the ocean.

Strait

• A narrow waterway between two larger bodies of water.

Island

• Land that is surrounded by water.

Slough

• A tidal waterway that creates a muddy marshland and usually connects other tidal areas.

Tributary

• A stream or river that flows into a larger river.

Headwater

• The source of a stream or river.

River Mouth

• Where a stream or river flows into a sea, lake, reservoir or ocean.