tree vs forest

tree and forest both are nouns.

tree (noun)	forest (noun)
a tall perennial woody plant having a main trunk and branches forming a distinct elevated crown; includes both gymnosperms and angiosperms	the trees and other plants in a large densely wooded area
a figure that branches from a single root	land that is covered with trees and shrubs

tree (verb)	forest (verb)
force a person or an animal into a position from which he cannot escape	establish a forest on previously unforested land
plant with trees
chase an animal up a tree
stretch (a shoe) on a shoetree