pathway

A pathway is a route or course that connects places or stages in a process. The term is used in physical geography, biology, ecology, medicine, and social planning to describe both tangible routes and sequences of events or actions. In everyday language, a pathway often refers to a trail or sidewalk designed for movement between locations.

In the built environment, pathways are designed pedestrian routes, often paved or landscaped, enabling safe and efficient travel. They may be part of urban streetscapes, parks, campuses, or transit hubs, and can include features such as lighting, signage, and accessibility considerations for people with disabilities.

In biology, a pathway denotes a series of molecular or biochemical events that lead to a cellular outcome. Metabolic pathways involve enzymatic steps that convert substrates into products, such as glycolysis or the citric acid cycle. Signaling pathways transmit information from receptors to effectors, coordinating responses like growth, division, or apoptosis. Pathways are frequently depicted as networks with branch points, cross-talk, and regulatory feedback, and are cataloged in databases such as KEGG and Reactome.

In ecology and evolution, pathways describe routes of energy flow or material cycling through ecosystems, as well as migratory or dispersal routes. In education and career planning, the term is used metaphorically to describe stepwise routes toward goals, such as a training pathway or a policy pathway.