Medical Definition of dorsiflexion. : flexion in a dorsal direction; especially : flexion of the foot in an upward directionâcompare plantar flexion.
Willis Tower. The Willis Tower, built as and still commonly referred to as Sears Tower, is a 108-story, 1,450-foot (442.1 m) skyscraper in Chicago, Illinois, United States.
From the ground to the roof it is 442 meters (1,450 feet) tall. It was designed by Fazlur Khan and Bruce Graham. Willis Tower is the second-tallest building in the United States. It is the eighth-tallest freestanding structure in the world.