What does it mean to "vibrate"?

To "vibrate" refers to the action of shaking slightly and quickly, which accurately describes the physical phenomenon observed in various contexts, such as when a tuning fork is struck or when a phone alerts you with a notification. This motion involves rapid back-and-forth movements around a central point and can occur in both solid and fluid mediums.

The other options reflect different types of motion or states that do not align with the definition of vibrating. For example, remaining still and quiet contradicts the active nature of vibration, while slowly rotating in place refers to a completely different type of movement that is not characterized by rapid shaking. Becoming rigid implies a lack of movement, opposing the essence of vibration, which inherently involves dynamic activity. Thus, the correct understanding of "vibrate" encompasses the idea of quick, slight shaking.