What do definition queries do in ArcGIS Pro?

Definition queries in ArcGIS Pro are used to filter the features that are displayed in a map or scene based on specific attribute criteria. When a definition query is applied to a layer, only the features that meet the defined criteria will be drawn or rendered, while all other features are hidden from view. This functionality allows users to focus on a subset of the data that is relevant to their analysis or visualization, making it an essential tool for managing complex datasets.

The ability to filter drawn features is crucial when working with large datasets because it improves performance and enhances the clarity of the visual representation by reducing clutter. Users can, for example, set a definition query to display only features of a certain type, within a specific date range, or above a threshold value, thereby tailoring the map to specific needs or objectives.

The other options, while useful in their own contexts, do not accurately describe the purpose of definition queries. Enhancing layer symbology pertains to how features are visually represented, calculating statistics refers to summarizing data values within attributes, and reprojecting features involves changing the coordinate system of spatial data. None of these functions involve filtering which is the primary role of definition queries.