What is the meaning of distortion?

noun

• A change for the worse.
  • synonyms: deformation
• A shape resulting from distortion.
  • synonyms: distorted shape
• An optical phenomenon resulting from the failure of a lens or mirror to produce a good image.
  • synonyms: aberration, optical aberration
• A change (usually undesired) in the waveform of an acoustic or analog electrical signal; the difference between two measurements of a signal (as between the input and output signal. )
  • usage: "heavy metal guitar players use vacuum tube amplifiers to produce extreme distortion"
• The act of distorting something so it seems to mean something it was not intended to mean.
  • synonyms: overrefinement, straining, torture, twisting
• The mistake of misrepresenting the facts. .