Jungle. jungle is land covered with dense forest and tangled vegetation, usually in tropical climates.
   Application of the term has varied greatly during the past recent century. The word jungle originates from the Sanskrit word jaṅgala, meaning rough and arid.
   It came into the English language via Hindi in the 18th century. The term is prevalent in many languages of the Indian subcontinent, and the Iranian Plateau, where it is commonly used to refer to the plant growth replacing primeval forest or to the unkempt tropical vegetation that takes over abandoned areas.
   Because jungles occur on all inhabited landmasses and may incorporate numerous vegetation and land types in different climatic zones, the wildlife of jungles cannot be straightforwardly defined. One of the most common meanings of jungle is land overgrown with tangled vegetation at ground level, especially in the tropics.
   Typically such vegetation is sufficiently dense to hinder movement by humans, requiring that travellers cut their way through. This definition draws a distinction between rainforest and jungle, since the understorey of rainforests is typically open of vegetation due to a lack of sunlight, and hence relatively easy to traverse. Jungles may exist within, or at the borders of, tropical forests in areas where the woodland has been opened through natural disturbance such as hurricanes, or through human activity
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