Abstract <p>The impact of a star-shaped ring tab on the dispersion and mixing characteristics of a subsonic jet is studied. The unique tab geometry, with multiple apex edges, generates counter-rotating vortices of varying scales that interact with the shear layer. Experiments were performed at the nozzle jet exit Mach numbers of 0.4, 0.6, and 0.8, and the outcomes were compared with those of an uncontrolled free jet. The introduction of the star ring tab results in a notable reduction in the potential core length, approximately 30, 50, and 87.5% at the Mach numbers of 0.4, 0.6, and 0.8, respectively, accompanied by enhanced jet decay rates relative to the baseline configuration. The radial Mach number profiles and the contour plots highlight the increased jet spread and deflection from the geometric centerline. Thrust vectoring was achieved with deflection angles of 1.4° at the Mach number 0.4, and 2.9° at the Mach number 0.8. The findings demonstrate the potential of star ring tabs to improve the mixing efficiency, support the thrust vectoring, and contribute to noise reduction in subsonic jet applications.</p>