One who demonstrates anything, or proves beyond doubt. / The forefinger. / One who takes part in a demonstration; a protester. / One who demonstrates products in a retail environment; a merchandiser.

simple past tense and past participle of demonstrate

plural of demonstration

that serves to demonstrate, show or prove / given to open displays of emotion / (grammar) that specifies the thing or person referred to

A demonstrative adjective. / A demonstrative pronoun.

present participle of demonstrate

A participant in a demonstration.

plural of demonstrable

plural of demonstrative

The quality of being demonstrable.