Keskireunan

Keskireunan is a Finnish term whose literal meaning is “central boundary” or “mid-edge.” It appears primarily in Finnish-language sources and does not correspond to a single, widely adopted concept in international technical vocabularies. Consequently, its precise meaning varies by field and author.

In geometry and mathematical pedagogy, keskireunan is used informally to refer to a line or boundary that separates a central region from its surroundings. Examples include the line connecting midpoints of opposite sides in certain polygons or a central seam used in some tiling schemes to denote symmetry axes. In tessellations, it may denote a central dividing line that helps describe how a figure is partitioned or mirrored.

In geography and urban planning, keskireunan may describe a boundary that marks the urban core or central district within a municipality, distinguishing central areas from outlying neighborhoods in planning documents and zoning maps.

In textiles and manufacturing, the term can refer to a seam or fold running along the centerline of a component, used for alignment, stability, or aesthetic purposes.

Because keskireunan is not a standardized technical term, it is typically defined explicitly when it appears in a text. Variants and related concepts may be described differently across disciplines, so readers should consult domain-specific Finnish sources for exact usage. See also: incenter, midline, boundary, centerline.