What is the meaning of demonstration?

noun

• A show or display; the act of presenting something to sight or view.
  • usage: "the presentation of new data"; "he gave the customer a demonstration"
  • synonyms: presentation, presentment
• A show of military force or preparedness.
  • usage: "he confused the enemy with feints and demonstrations"
• A public display of group feelings (usually of a political nature. )
  • usage: "there were violent demonstrations against the war"
  • synonyms: manifestation
• Proof by a process of argument or a series of proposition proving an asserted conclusion.
  • synonyms: monstrance
• A visual presentation showing how something works.
  • usage: "the lecture was accompanied by dramatic demonstrations"; "the lecturer shot off a pistol as a demonstration of the startle response"
  • synonyms: demo