Dynamical masses refer to the measurement or determination of the mass of a celestial object, such as a star or a galaxy, through various dynamical methods. These methods typically involve observing the motion and gravitational interactions of objects in a system, such as stars in a stellar cluster or galaxies in a galaxy cluster, to infer the mass of the central object or system. Dynamical masses are important for understanding the dynamics and evolution of celestial objects and systems, as well as for testing theoretical models of gravity and cosmology.