Läpivirta

Läpivirta (from läpi "through" + virta "flow") is a Finnish noun describing throughflow or pass-through—the movement or transmission of something through a medium, system, or boundary. The exact sense depends on context, but the core idea is that an element can cross from one side to the other without being completely transformed or halted.

In hydrology and environmental science, läpivirta describes water or solutes moving through soil or porous media from one side to the other. It is a key component in models of infiltration, drainage, and groundwater flow, and helps explain how rainfall or irrigation influences subsurface conditions and surface runoff.

In economics and business, läpivirta is used to describe price pass-through: how changes in costs, taxes, or tariffs are transmitted to final prices charged to consumers or downstream buyers. The degree of pass-through depends on market competition, demand, and regulatory factors.

In engineering and signal processing, läpivirta can denote a direct or nearly unaltered signal path through a device, subsystem, or network. The term is used to contrast through-flow with signal modification, filtering, or attenuation.

See also: pass-through, throughflow.