Velocity

Noun

1. A vector quantity that denotes the rate of change of position with respect to time, combining speed with a directional component.

   "A car racing in a circle may retain the same speed while continually changing its velocity."

2. A rapidity of motion.

   "The train was travelling at a slower velocity than usual."

3. The rate of occurrence.
4. The number of times that an average unit of currency is spent during a specific period of time.
5. The value corresponding to how hard a key is struck on a MIDI controller or keyboard.