1. Forest, grove, wood refer to an area covered with trees. A forest is an extensive area, preserving some or all of its primitive wildness and usually having game or wild animals in it: Sherwood Forest; the Black Forest. A grove is a group or cluster of trees, usually not very large in area and cleared of underbrush. It is usually tended or cultivated: a shady grove; a grove of pines; an orange grove; a walnut grove. Woods (or a wood ) resembles a forest but is a smaller tract of land, less wild in character, and generally closer to civilization: lost in the woods; a wood covering several acres.

Did you mean rainforest?