stín

Stín is a Czech noun meaning shadow or shade. It describes the region where direct light is blocked by an opaque object, resulting in reduced illumination on a surface. A shadow appears whenever light is obstructed, and its characteristics depend on the light source and the geometry of the scene.

In simple terms, a shadow forms when light cannot travel in a straight line from the source to a surface. With a point light source, the shadow’s outline is close to the silhouette of the occluding object. For an extended light source, there is a central dark area called the umbra and a surrounding lighter zone called the penumbra. The size and shape of shadows depend on the relative positions of the light source, the object, and the surface, and shadows change as those positions move or as the light source varies.

Linguistic and cultural context: In Czech, stín is used for literal shadows as well as for shade more generally. Related terms include stínění (shading or shielding) and stinný (shady, dim). The word is cognate with similar terms in other Slavic languages and forms part of a broader family of words for light and darkness.

Applications and examples: Shadows influence daily life by indicating the sun’s position, aiding navigation of space, and contributing to the mood in photography and visual arts. In astronomy, shadows are central to understanding eclipses, as the Earth’s shadow causes lunar eclipses and the Moon’s shadow causes solar eclipses. In architecture and urban planning, controlling shade helps reduce glare and heat gain, shaping the design of streets, courtyards, and building orientations.