acceleration

noun

1 the car's acceleration is sensational:

speeding up, increasing speed, increase in speed, gain in momentum, gathering speed, opening up;

technical rate of change of velocity.

▷antonyms deceleration, slowing down.

2 there was some acceleration of the process:

hastening, speeding up, quickening, stepping up, advancement, furthering, furtherance, forwarding, promotion, boosting, boost, stimulation, spur, aid, assistance, facilitation, easing, simplification, expedition, precipitation.

3 an acceleration in the divorce rate:

increase, rise, advance, leap, surge, escalation, spiralling, worsening.

acceleration Oxford Dictionary of English