Natural world

3. a large natural stream of water flowing in a channel to the sea, a lake, or another such stream.
6. a large area of flat unforested grassland in southeastern Europe or Siberia.
8. a slowly moving mass or river of ice formed by the accumulation and compaction of snow on mountains or near the poles.
9. a large body of water surrounded by land.
12. a structure or place made or chosen by a bird for laying eggs and sheltering its young.
14. a large open area of country covered with grass, especially one used for grazing.
15. an area of land overgrown with dense forest and tangled vegetation, typically in the tropics.

1. a large area covered chiefly with trees and undergrowth.
2. a woody plant that is smaller than a tree and has several main stems arising at or near the ground.
4. plants considered collectively, especially those found in a particular area or habitat.
5. a very large expanse of sea, in particular, each of the main areas into which the sea is divided geographically.
7. the natural home or environment of an animal, plant, or other organism.
10. having little or no rain; too dry or barren to support vegetation.
11. a large natural elevation of the earth's surface rising abruptly from the surrounding level; a large steep hill.
13. the expanse of salt water that covers most of the earth's surface and surrounds its landmasses.