I suppose I've never considered a ball more than just a spherical object. However, now that you've cast some light on the subject it does appear to be more than just that. Giving it some thought it seems to have subjective qualities enough so that non-spherical objects can be appropriately termed a "ball". Perhaps
emergence can explain the balls multitude of forms and uses.
In philosophy, systems theory, science, and art, emergence is a process whereby larger entities, patterns, and regularities arise through interactions among smaller or simpler entities that themselves do not exhibit such properties.
https://en.wikipedia.org/wiki/Emergence