Part of speech: Adjective
given to or marked by the open expression of emotion
Example: an affectionate and demonstrative family
Part of speech: Adjective
serving to demonstrate
Illustrative, Demonstrative, Demonstrative pronoun
The word "demonstrative" comes from Middle French démonstratif, which comes from Middle English demonstratif.
The Norman Conquest of 1066 brought thousands of French words into English overnight.