tower
The Keep
skyscraper.
Building as in the action: constructing Building as in the noun: construction, architecture
edifice
Edifice
tall
Sears Tower, but it may be a different name
The Burj Khalifa is the tallest building in the world. It is 2716 feet tall.
saguaro
smokestacks
phineas and ferb
Building block
Gross Building Area