utility

1. In economics, a measure of satisfaction. For example, some middle-aged men gain substantial utility from driving sports cars, even though these vehicles are expensive and impractical.
2. A business that provides an essential service, generally under government regulation. Electric companies, gas transmission firms, and local telephone companies are utilities.
3. A software program designed to perform a specific task related to managing a computer's resources. For example, a defragmenter program can detect and restructure fragmented files.