An operational definition is a clear and specific explanation of how a concept or variable will be measured or identified in a study. It helps researchers ensure that everyone understands the terms in the same way, making it easier to replicate studies and compare results. For example, if a study is examining stress, the operational definition might specify that stress is measured by the number of times participants report feeling anxious in a week. Operational definitions are crucial in research because they provide clarity and precision. By defining variables like happiness or intelligence in measurable terms, researchers can collect data that is consistent and reliable. This process enhances the validity of the research findings and allows for better communication of results within the scientific community.