疾速

jísù
  1. very fast
  2. at high speed

CEDICT

速度極快。

重編國語辭典

Entry Composition

1 疾 jí
  1. (bound form) disease; ailment
  2. (bound form) swift
  3. (literary) to hate; to abhor
2 速 sù
  1. fast
  2. rapid
  3. quick
  4. velocity

Related entries

飛快 fēikuài
  1. very fast
  2. at lightning speed
  3. (coll.) razor-sharp
跑得飛快

Run like the wind.

Run very fast.

Source: Tatoeba

飛也似的 fēiyěshìde
  1. lit. as if flying
  2. very fast