The term spatially crosses denotes a spatial relation between two given geometries that has the following properties:
- The two geometries intersect
- Their intersection results in a geometry that has a dimension that is one less than the maximum dimension of the two given geometries
- Their intersection is not equal to either of the two given geometries
CROSSES() is based on the original MySQL implementation, and uses object bounding rectangles, while ST_CROSSES() uses object shapes.