IPA: //ˈruːftriː//
KK: /ˈrufˌtri/
The top part of a roof, often where the two sides meet.
The architect designed a beautiful rooftree that added elegance to the house.
Rooftree is formed from "roof" (from Old English *hrof*, meaning the top covering of a building) and "tree" (from Old English *treow*, meaning a woody plant). The word refers to the structure that supports the roof, metaphorically likening it to a tree that supports the top of a house.
Think of a 'roof' as the top covering of a building and a 'tree' as something that supports or stands tall. This helps you remember that 'rooftree' refers to the structure that supports the roof.
No commonly confused words.