Definitions of demonstration:

• noun:   a show of military force or preparedness

  Example: "He confused the enemy with feints and demonstrations"

• noun:   a public display of group feelings (usually of a political nature)

  Example: "There were violent demonstrations against the war"

• noun:   proof by a process of argument or a series of proposition proving an asserted conclusion
• noun:   a visual presentation showing how something works

  Example: "The lecture was accompanied by dramatic demonstrations"

• noun:   a show or display; the act of presenting something to sight or view

  Example: "He gave the customer a demonstration"