Hill

A hill is a landform that is higher than the surrounding terrain and that is smaller than a mountain. Hill is a highland of much lower elevation than a mountain. Normally it is not as steep as a mountain. By definition, a hill is often described as being lower than 610 meters (about 2,000 feet). The surface of a hill is much more stable than that of a dune. Hill have long been used for hill forts
Pictures

Some hills are very small like this ant hill
Other websites
Media related to Hills at Wikimedia Commons
The Simple English Wiktionary has a definition for:
hill.