Dreierlinie

Dreierlinie is a German term literally meaning "three-line" and is used in various fields to denote a line, route, or boundary that involves three elements, endpoints, or connections. It is not tied to a single fixed definition but depends on context.

In sports, particularly basketball, Dreierlinie commonly refers to the three-point line. A successful field goal made from beyond this line counts as three points. The exact distance of the line varies by competition and court design; different leagues use different measurements, and the line may be an arc rather than a straight segment.

In urban planning and public transportation, Dreierlinie can describe a service line or corridor intended to connect three main hubs or regions. Such a line is planned to facilitate transfers among multiple lines, increase network flexibility, and improve travel times. The term is used descriptively in planning documents and is not a standard technical term with a universal specification.

In other domains, the term can appear metaphorically to denote three intersecting or parallel lines, pillars, or principles that support a system or argument. As a compound noun, its precise meaning must be inferred from surrounding text.

See also: three-point line; tri-linear networks; multi-line systems.