unidirection

Unidirection is a term describing the state or quality of proceeding in a single direction; it is opposite to bidirection or multidirection. It is often used in physics, engineering, and information theory to denote one-way behavior.

The term is formed from Latin uni- “one” and directio “direction.” In usage, “unidirection” as a noun is less common than the adjective “unidirectional” or the noun “unidirectionality.” Some disciplines treat it as a property of systems or components designed to favor motion, flow, or transmission in one direction.

In electronics, unidirectional elements such as diodes and rectifiers pass current predominantly in one direction, preventing reverse flow. In fluid dynamics and hydraulics, devices may enforce unidirectional flow using check valves or pumps. In acoustics and electromagnetism, unidirectional emission or reception refers to preferential propagation or sensing in a single orientation. In computer science, unidirectional data flow describes architectures where data moves from a source to a sink without feedback loops, as opposed to bidirectional or cyclic flows.

Limitations: Real systems are rarely perfectly unidirectional; most exhibit some leakage or backflow. Design considerations aim to maximize forward directionality while minimizing reverse transmission.

See also: Diode; Rectifier; Check valve; Unidirectional data flow; One-way system.