Definission: A landform that extends above the surrounding terrain in a limited area. A mountain is generally steeper than a hill, but there is no universally accepted standard definition for the height of a mountain or a hill although a mountain usually has an identifiable summit and a local relief of more than 300m.
Definission: A sheet of saline water separated from the open sea by sand or shingle banks. The sheet of water between an offshore reef, especially of coral and mainland. The sheet of water within a ring or horseshoe shaped atoll.
Definission: An area of land of low topographic relief that historically supported grasses and herbs, with few trees, and having generally a mesic (moderate or temperate) climate. Dominated by tall grasses (contrast steppe).
Definission: A grassland biome is a terrestrial biome which includes, across its entire spatial extent, an unbroken layer of grasses (Gramineae), sedges (Cyperaceae) or rushes (Juncaceae).
Definission: A habitat that is in or on a body of water containing low concentrations of dissolved salts and other total dissolved solids (<0.5 grams dissolved salts per litre).