IPA: /ˈtriːtɒp/
KK: /ˈtriːtɑːp/
The highest part of a tree where the branches and leaves grow.
The bird built its nest in the treetop, safe from predators.
Treetop is formed from "tree" (from Old English *treow*, meaning a perennial plant with an elongated stem) and "top" (from Old English *top*, meaning the highest point). The word "treetop" refers to the highest point of a tree.
Imagine the highest point of a tree — that's what treetop means, combining the idea of a 'tree' and its 'top'.