1. of, relating to, or used for demonstration or showing something by example
Usage: formal; often used in educational or technical contexts
2. relating to or involving public protest or expression of opinion
Usage: less common than 'demonstrative' in this sense

Examples

• The teacher used a demonstrational approach to show how the experiment works.
• The software includes demonstrational videos to help new users learn the interface.
• A demonstrational model was built to test the engineering concept before full production.
• The group organized a demonstrational event to raise awareness about climate change.
• The scientist gave a demonstrational lecture with live examples and visual aids.