| A | B |
|---|
| alluvial fan | A large fan-shaped deposit of alluvial sediment over which a stream flows |
| archipelago | A chain or set of islands grouped together. |
| atoll | A ring-shaped island, with a lagoon in the middle, which was formed by the eruption and collapse of a volcano. |
| basin | A topographic rock structure whose shape is concave downwards |
| canyon | A narrow chasm with steep cliff walls, cut into the earth by running water. |
| cape | A point or extension of land jutting out into water as a peninsula or as a projecting poin |
| cay | A small, low island composed largely of coral or sand. |
| desert | Biome that has plants and animals adapted to survive severe drought conditions. In this habitat, evaporation exceeds precipitation and the average amount of precipitation is less than 25 centimeters a year |
| erg | A large, shifting sand dune, or set of dunes, found in desert regions. 2. A geologic measurement of time; shorter than an eon but longer than a period. |
| "Fall Line" | The physical boundary between the piedmont and coastal plain regions of the U.S.’ Eastern Seaboard. |
| Great Rift Valley | A large system of rift valleys in eastern Africa and the Middle East, the largest in the world, that runs for about 3,000 miles (4,285 km) from the Jordan valley in Syria into Mozambique. It is marked by a chain of lakes and a series of volcanoes, including Mount Kilimanjaro |
| highlands | An area of high or mountainous land. |
| island | A piece of land surrounded by water. |
| isthmus | A narrow strip of land with sea on either side, forming a link between two larger areas of land. |
| lowlands | An area of land that is low in relation to the surrounding country. adj. Relating to or characteristic of low, usually level land. |
| mountain | A large natural elevation of the earth's surface rising abruptly from the surrounding level. |
| mountain range | A line of mountains connected by high ground. |
| pass | A gap in a mountain range |
| peninsula | A landform that has coastal waters on three sides, but is connected to a mainland by an isthmus. |
| piedmont | Foothill regions found at the base of mountains that gradually transition to plains |
| plain | A large area of flat land with few trees |
| plateau | Also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain |
| rift valley | A long, straight, deep valley produced by the separation of crustal plates |
| savanna | A flat grassland found in tropical or subtropical regions. Savanna is also a biome |
| steppe | A type of vegetation region (i.e. – a biome), characterized by plains with prairies, savannas, or scrubland, found in temperate climate zones; |
| Tiaga | The swampy coniferous forest of high northern latitudes, esp. that between the tundra and steppes of Siberia and North America. |
| tundra | A vast, flat, treeless Arctic region of Europe, Asia, and North America in which the subsoil is permanently frozen |
| valley | A low area of land between hills or mountains, typically with a river or stream flowing through it. |
| volcano | A mountain or hill, typically conical, having a crater or vent through which lava, rock fragments, hot vapor, and gas are or have been erupted from the earth's crust. |
| caldera volcano | A large, basin-like depression resulting from the explosion or collapse of the center of a super volcano. |
| abyssal plain | A flat, level area of the sea floor found in the deepest parts of ocean basins. |
| aquifer | An underground reservoir of water which can be extracted for surface use. |
| bay | A body of sheltered water found in a crescent shaped coastal configuration of land. Larger than a cove but smaller than a gulf |
| cataract | A large or high waterfall. |
| channel | A length of water wider than a strait, joining two larger areas of water, esp. two seas. |
| continental shelf | The area of seabed around a large landmass where the sea is relatively shallow compared with the open ocean. |
| fjord | Inlets found along mountainous coastlines where glaciers have carved narrow, deep valleys and troughs that are now filled with a brackish mixture of fresh water |
| geyser | A hot spring in which water intermittently boils, sending a tall column of water and steam into the air. |
| glacier | a large long lasting accumulation of snow and ice that develops on land. |
| gulf | A deep inlet of the sea almost surrounded by land, with a narrow mouth. |
| ocean | The expanse of salt water that covers most of the earth's surface and surrounds its landmasses. |
| sea | large body of water partially surrounded by land |
| strait | A narrow passage of water connecting two seas or two large areas of water. |
