In cartography, the displacement or movement of features so that they do not overlap when displayed at a given scale. For example, a road can be offset from a river if the symbols are wide enough that they overlap.
In symbology, the shift of the origin or insertion point of a symbol in an x and/or y direction.
In ArcGIS, a change in or the act of changing the z-value for a surface or features in a scene by a constant amount or by using an expression. Offsets may be applied to make features draw just above a surface.