Velocity is defined as:

Velocity is defined as the rate of change of an object's position with respect to time, and it specifically incorporates both magnitude and direction. This definition emphasizes that velocity is not just about how fast an object is moving, which is what speed represents, but also indicates in which direction that motion is occurring.

For a velocity measurement, one would consider how far the object travels in a given time frame, and it is crucial to state the direction of travel, such as "5 meters per second east." This makes velocity a vector quantity, which means it has both a numerical value (magnitude) and a specific direction.

In contrast, distance over time only represents speed, which lacks directional information, making it insufficient to define velocity on its own. Speed without direction is simply the rate at which an object covers ground, once again missing the directional aspect. Finally, magnitude of acceleration refers specifically to how quickly an object's velocity changes, not to the velocity itself. Thus, the correct understanding of velocity involves defining it as distance in a specific direction over time.