This is the 2072nd most frequent Japanese word.
加速
"加速" means "acceleration" or "to speed up."
加速 is used here as a verb to describe the car increasing its speed.
車はスムーズに加速しました。
The car accelerated smoothly.
加速 is used here to indicate the enabling of quicker processes.
新しいプロセッサーが計算速度を加速させました。
The new processor accelerated the calculation speed.
加速 is used here as a noun indicating the general increase in pace.