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.
Willis Tower. Willis Tower, formerly (1973â2009) Sears Tower, skyscraper office building in Chicago, Illinois, located at 233 South Wacker Drive, that is one of the worldâs tallest buildings. The Sears Tower opened to tenants in 1973, though construction was not actually completed until 1974.