whizbang

/HH W IH1 Z B AE1 NG/
noun
  1. 1

    A type of firework that made a whiz before exploding

  2. 2

    A small artillery shell

  3. 3

    (by extension) Someone or something that holds an explosive amount of success, skill or effectiveness.

Source: https://en.wiktionary.org/wiki/whizbang