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Предлог "поперек": Значение и употребление
According to the Dictionary of the Russian Language (MAS), the preposition "poperek" (across) indicates the direction of an action based on the width of something (1987, 3, 293). The width of an object usually implies its length (and "across" is contrasted with "lengthwise"), so the usual use of this preposition is associated with objects that are elongated, but not like a string, that is, those with a clear dimension not only in length but also in width. However, its use with the names of landmark objects that are not characterized by a distinct width is quite traditional: across a string, a vein, or a fiber. Modern usage offers non-canonical (relative to the classical synchronic dictionary interpretation) uses of this preposition, ranging from associations with objects lacking a pronounced dimensional contrast, fixed boundaries, or strict form (across the sky, sea, taiga, universe), to contextual substitution of the preposition "along" (across a gate, door, or entrance). In the Russian linguistic worldview, openings (portals) have no length dimension; their primary dimension is width, and, when applied to openings, "along" and "across" are associated with the same spatial position (the goalkeeper lies across the hockey goal, that is, in the direction from goalpost to goalpost; the storm drain runs along the goal, that is, in the direction from post to post). The difference lies in the position inside or outside the landmark. The prepositions contrasted in dictionaries have a specific collocation with the word "lob" (forehead): a deep wrinkle runs along the forehead, and a person with a wide band across the forehead (in both cases, the reference is to the direction along the width of the body, perpendicular to the person's height).