Which term describes the action of a pendulum swinging?

The term that accurately describes the action of a pendulum swinging is "oscillate." When a pendulum swings back and forth around a central point, it moves in a repetitive manner, which is characteristic of oscillation. This action involves the pendulum moving away from its resting position and then returning, creating a periodic motion that is typical of oscillatory systems.

In contrast, "rotate" refers to an object turning around an axis without changing its position linearly, which doesn't apply to the movement of a pendulum. "Pivot" indicates a point of rotation or the action of turning around that point, but it doesn't fully capture the complete back-and-forth motion of a pendulum. "Revolve" suggests moving in a circular orbit around a point, which is not representative of a pendulum's swinging motion either, as it does not create a circular path but rather a linear oscillation. Therefore, "oscillate" is the most fitting term for describing the swinging action of a pendulum.