jungle
A thick, tangled forest in a hot, rainy place.
A jungle is a dense, tangled forest found in hot, humid regions near the equator, where trees, vines, and plants grow so thickly that sunlight barely reaches the ground. In a true jungle, vegetation crowds together in a wild tangle, making it difficult to walk through without cutting a path.
The word comes from a Hindi word meaning “wasteland” or “uncultivated land,” but jungles are far from waste: they teem with life. Monkeys swing through the canopy, colorful birds call from the branches, and insects hum constantly in the thick, moist air. The Amazon rainforest in South America contains vast stretches of jungle, as do parts of Southeast Asia and central Africa.
People often confuse jungles with rainforests, but they're not quite the same. A rainforest is any forest with heavy rainfall; a jungle specifically refers to the thick undergrowth that develops where lots of light reaches the ground, usually at a rainforest's edge or in clearings.
We also use jungle metaphorically to describe any confusing, competitive, or difficult situation. Someone might call a tough middle school “a jungle” or describe a complicated video game level as “a jungle out there.” The phrase “the law of the jungle” refers to survival of the strongest, though ironically, real jungles depend on cooperation between species as much as competition does.