ve·loc·i·ty 
/vəˈlɑ:səti/ noun
plural ve·loc·i·ties /vəˈlɑ:səti/ noun : quickness of motion : speed [count] ▪ particles moving at high velocities [noncount] ▪ measuring the velocity of sound ▪ the velocity of a bullet ▪ His pitches have great velocity. [=his pitches are very fast]
