unused

Unused is an adjective meaning not used or not utilized. It describes objects, resources, or opportunities that have not been brought into service, either because they were unnecessary, set aside, or not yet employed. In everyday usage, something unused is often in its original condition, sometimes unopened or unsold.

In economics and operations, unused resources can refer to spare capacity, idle labor, or inventory that has not been consumed. Monitoring unused capacity helps organizations gauge potential efficiency improvements and inform investment decisions. In energy and environmental contexts, unused energy may result from curtailment, storage limitations, or mismatches between supply and demand, while unused land represents potential for development, conservation, or redevelopment.

In computing and software, unused can describe code, variables, or memory that are present but not executed or referenced. Compilers and analysis tools frequently warn about unused variables, functions, or imports, highlighting opportunities to optimize or clean up code. In data management, unused data may be archived or deleted to reclaim storage resources.

Etymology: The word is formed by the prefix un- attached to the adjective used. The form used derives from Old French usé, from Latin usus, with the modern sense of not having been employed.

See also: wasted resources, inventory management, idle capacity, unused variable, unused land.