 Put another way, one can define the predicate x accelerates as trajectory(x) has-non-zero-rate-of-change-from-straightness, where trajectory maps bodies onto their trajectories in Galilean spacetime. And this predicate, defined this way, applies to the water in Newton’s bucket if and only if it is rotating, according to Newtonian mechanics formulated in terms of the geometry of Galilean spacetime; it is the mechanically relevant sense of accelerate in this theory. But this theoretical formulation and definition have been given in terms of the geometry of spacetime, not in terms of the relations between bodies; acceleration is ‘absolute’ in the sense that there is a preferred (true) sense of acceleration in mechanics and which is not defined in terms of the motions of bodies relative to one another. Note that this sense of ‘absolute’ is broader than that of motion relative to absolute space, which we defined earlier. In the remainder of this article we will use it in this new broader sense. The reader should be aware that the term is used in many ways in the literature, and such equivocation often leads to significant misunderstanding.