demonstrator
//ˈdɛmənˌstreɪtər//
Noun
demonstratorSingular
demonstratorsPlural
1
A person who takes part in a public protest or march to express opposition or support for a cause.
Thousands of demonstrators gathered in the city center to protest against the new policy.
2
A person who shows or explains how something works or is done, especially in a teaching or sales context.
The demonstrator showed us how to use the new kitchen appliance.
3
A product, especially a vehicle, used for demonstration purposes to potential buyers.
The dealership offered a discount on the demonstrator model.