The invention is a moving-slider rotary piezoelectric microactuator as the secondary actuator for a dual-stage actuator disk drive. The microactuator has a substrate attached to the disk drive suspension and a rotatable frame that supports the slider, so the head-suspension assembly includes the suspension, the microactuator and the slider with attached read/write head. The rotatable frame is attached to a fixed post on the substrate by relatively stiff torsional springs. A piezoelectric driver having a fixed end attached to the substrate provides bidirectional linear displacement of its movable end. The microactuator has a displacement amplification mechanism that includes a connecting rod and a linkage that translates the linear displacement of the driver to amplified orthogonal linear displacement of the rod. The connecting rod is attached to the rotatable frame at a radial distance to cause rotary movement of the frame, and thereby cross-track displacement of the read/write head on the slider.