Drive device (100), notably for a horology calendar system (200), the drive device including a drive mobile (10) for driving an element (4) that is to be driven, notably a calendar element, the drive mobile being intended to be mounted so that it can rotate about an axis (A1) and including (a) a support (11); (b) a first flank (f11) for driving the element that is to be driven; and (c) a second flank (f12′) arranged in such a way as to receive an action to retract the drive mobile, notably extending orthoradially or substantially orthoradially with respect to the axis (A1); the mobile comprising a slide link (111, 121; 11, 120; 110, 120′) connecting the second flank to the support.