Source : Webster's Revised Unabridged Dictionary (1913)

Whiz \Whiz\, v. i. [imp. & p. p. {Whizzed}; p. pr. & vb. n.
   {Whizzing}.] [Of imitative origin. ???. Cf. {Whistle}, and
   {Hiss}.]
   To make a humming or hissing sound, like an arrow or ball
   flying through the air; to fly or move swiftly with a sharp
   hissing or whistling sound. [Written also {whizz}.]

         It flew, and whizzing, cut the liquid way. --Dryden.

Whiz \Whiz\, n.
   A hissing and humming sound.

         Like the whiz of my crossbow.            --Coleridge.

Source : WordNet®

whiz
     n 1: someone who is dazzlingly skilled in any field [syn: {ace},
          {adept}, {champion}, {sensation}, {maven}, {mavin}, {virtuoso},
           {genius}, {hotshot}, {star}, {superstar}, {whizz}, {wizard},
           {wiz}]
     2: a buzzing or hissing sound as of something traveling rapidly
        through the air; "he heard the whiz of bullets near his
        head"
     v : make a soft swishing sound; "the motor whirred"; "the car
         engine purred" [syn: {whizz}, {whirr}, {whir}, {birr}, {purr}]
     [also: {whizzing}, {whizzes}, {whizzed}]