swift·ness /ˈswɪf(t)nəs/
  迅速,敏捷
  Swift·ness, n. The quality or state of being swift; speed; quickness; celerity; velocity; rapidity; as, the swiftness of a bird; the swiftness of a stream; swiftness of descent in a falling body; swiftness of thought, etc.
  ◄ ►
  swiftness
       n : a rate (usually rapid) at which something happens; "the
           project advanced with gratifying speed" [syn: speed, fastness]