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.
Six years ago, the Sears Tower (now Willis) added The Ledge, four glass boxes on the western face of the 103rd floor, into which a small group can step and see the city underfoot (or underhead â more on that later). More than a million do so every year.