wall (noun) 1. any of various permanent upright constructions having a length much greater than the thickness and presenting a continuous surface except where pierced by doors, windows, etc.: used for shelter, protection, or privacy, or to subdivide interior space, to support floors, roofs, or the like, to retain earth, to fence in an area, etc. Editor's Note: "Defined" is an occasional series exploring the definitions of words via photography. -- By Leanne Burden Seidel
A bicyclist passes a mural along the BeltLine, Feb. 17, in Atlanta. The 2.25-mile-long paved trail east of downtown attracts a steady stream of joggers, dog-walkers and cyclists to take in spectacular views of the skyline and public art installations as well as a slice of established neighborhoods that were once only seen by riding a freight train. (David Goldman/Associated Press)