What is the meaning of slam-bang?

adjective

• Violent and sudden and noisy.
  • usage: "a slam-bang collision"

adverb

• In a careless or reckless manner.
  • usage: "the shelves were put up slapdash"
  • synonyms: slapdash
• With heedless speed.
  • usage: "yachts ran slap-bang into the convoy at 15 knots an hour"
• In a violent or sudden or noisy manner.
  • usage: "the pans fell slam-bang and woke the whole house"
  • synonyms: slap-bang