How to say "accelerate" in Japanese

• 早めるはやめるJLPT N1approx.Common
  ichidan verb, transitive verbCovers accelerating in the physical sense of quickening or speeding up something's pace, such as one's step. The most direct choice when you simply make something move or proceed faster.
  我々われわれはふだんより足あしを速はやめて歩あるいた。↗

  We walked more quickly than usual.
• 促すうながすJLPT N1approx.Common
  godan verb, transitive verbCovers accelerating in the sense of hastening or stimulating something like growth or development; it suggests prompting or urging the process along rather than directly speeding it up. Also commonly means simply to urge or prompt someone.
  この曲きょくは眠ねむりを促うながしてくれます。↗

  This music helps me to fall asleep.

Use 「早める」 to speed up something concrete like one's pace; use 「促す」 when hastening or stimulating something abstract such as growth or development, with a nuance of prompting it along.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 早めるはやめるto quicken (e.g. one's step)
• 促すうながすto stimulate (e.g. growth)