fastness, swiftness, speed - a rate (usually rapid) at which something happens; "the project advanced with gratifying speed"

getaway, pickup - the attribute of being capable of rapid acceleration; "his car has a lot of pickup"

precipitation - an unexpected acceleration or hastening; "he is responsible for the precipitation of his own demise"

hurrying, speeding, speed - changing location rapidly

natural philosophy, physical science, physics - the science of matter and energy and their interactions

centripetal acceleration - the acceleration toward the center that holds a satellite in elliptical orbit

rate - a magnitude or frequency relative to a time unit; "they traveled at a rate of 55 miles per hour"; "the rate of change was faster than expected"