demonstrator

noun

dem·​on·​stra·​tor ˈde-mən-ˌstrā-tər 

: one that demonstrates:

a

: a product (such as an automobile) used to demonstrate performance or merits to prospective buyers

b

: a person who engages in a public demonstration

Examples of demonstrator in a Sentence

Thousands of demonstrators marched through the streets.

Recent Examples on the Web

The Islamic Republic of Iran’s supreme leader, Khamenei, would order just weeks later the murder of thousands of Iranian demonstrators. —Benjamin Weinthal, FOXNews.com, 5 Feb. 2026

More demonstrators were also reported near Temple and Alameda streets by the federal building, where a dispersal order was issued. —Anissa Rivera, Daily News, 5 Feb. 2026

In 2023, the firm was separately contracted to develop a linear aerospike rocket engine for a spaceplane demonstrator. —Chris Young, Interesting Engineering, 5 Feb. 2026

The speech marked a decisive break from his reformist persona and aligned him publicly with the regime’s violent crackdown on demonstrators. —Nic Robertson, CNN Money, 4 Feb. 2026

Word History

Etymology

demonstrate + -or entry 1

First Known Use

1593, in the meaning defined above

Phrases Containing demonstrator

• counter-demonstrator

Rhymes for demonstrator

• activator
• actuator
• agitator
• alligator
• allocator
• alternator
• animator
• annotator
• applicator
• arbitrator
• aspirator
• aviator

Kids Definition

demonstrator

noun

dem·​on·​stra·​tor ˈdem-ən-ˌstrāt-ər 

1

: a person who makes or takes part in a demonstration

2

: a manufactured article (as an automobile) used for purposes of demonstration

Medical Definition

demonstrator

noun

dem·​on·​stra·​tor ˈdem-ən-ˌstrāt-ər 

: a teacher or teacher's assistant who demonstrates principles or theories studied (as by dissection, experiment, or chemical preparation)