加速

jiāsù
to accelerate; to speed up; to expedite

CEDICT

Entry Composition

1 加 jiā
  1. to add
  2. (math.) plus
  3. to increase; to augment
  4. (used before a disyllabic verb, often after an adverb like 不 bù, 大 dà, 稍 shāo etc, to indicate that the action applies to sth previously mentioned, as in 稍加改良 shāojiāgǎiliáng "make some minor improvements to (it)")
2 速 sù
  1. fast
  2. rapid
  3. quick
  4. velocity