BLEACHER

'Bleachers' is a term used to describe the raised, tiered stands found by sports fields or at other spectator events in the United States and Canada. Bleachers are long rows of benches, often consisting of alternating steps and seats. They range in size from small, modular, aluminum stands that can be moved around soccer or field hockey fields to large permanent structures that flank either side of a football field. Bleachers are hollow underneath, aside from their support structures. Some bleachers have locker rooms underneath them. In indoor gymnasia, bleachers can be built in so that they slide on a track or on wheels and fold in an accordion-like, stacking manner. The seats of these bleachers are often made of wood.
A key feature of bleachers is that they are typically uncovered, i.e. unprotected from the sun; thus the seats, and the fans themselves, are subject to "bleaching" from prolonged exposure to solar radiation. Some sources claim that the term is primarily derived from that feeling of being bleached by the sun while sitting in them.^[1] However, ''The Dickson Baseball Dictionary'' discusses the term in greater depth. The open seating area was originally called the "bleaching boards", as early as 1877. By the early 1900s, the term "bleachers" was being used for both the seating area and its inhabitants. Thus, Dickson lists the fans themselves as "bleachers", as a ''secondary'' definition. Other terms, such as "bleacher seats" and "bleacher entrance" and "a home run into the bleachers", are ambiguous enough that they could refer to either the seats or the fans. However, in modern usage the term "bleachers" almost always refers to just the seating area, and its participants may be called "bleacher fans", or "bleacherites", or (in Chicago) "bleacher bums".
In baseball stadiums, the bleachers are usually located beyond the outfield fences. However, center-field bleachers are located in the line of sight of the batter, and the presence of fans makes it difficult for the batter to pick out the ball. As a result, most stadiums have vacant areas or black backgrounds where the seats would be. Yankee Stadium has featured black-painted vacant bleachers -- nicknamed ''the black'' by baseball fans -- since it reopened in 1976 after a two-year renovation. In the original Stadium, the center-field section of the bleachers was originally occupied, though from the 1950s they were obscured with a portable screen. Bleachers can be used for all sports known.
The term ''"under the bleachers"'' is imbued with cultural meaning from the post-war era of American high school football stars and cheerleaders. In the sexually conservative society of post-war America, some students would find places like the bleachers at the football field, or a secluded car park, to interact socially and sexually with their peers. The "bleachers" have been given cultural connotations of the innocence of high school, youth, and this period of American history, as well as the defiance, excitement, and intrigue of stolen kisses and forbidden love. The British equivalent is "behind the bike sheds".
1. American Heritage Dictionary