A new method to construct aggregation functions is introduced. These aggregation functions are called wbiconic aggregation functions with a given diagonal (resp. opposite diagonal) section and their construction method is based on linear interpolation on segments connecting the diagonal (resp. opposite diagonal) of the unit square and the points (0, 1) and (1, 0) (resp. (0, 0) and (1, 1)). Special classes of biconic aggregation functions such as biconic semi-copulas, quasi-copulas and copulas are studied in detail.