A substance that initiates a physiological response when combined with a receptor.

उत्तेजक

English Usage: The agonist drug effectively binds to the receptor and stimulates a response in the body.

Hindi Usage: उत्तेजक दवा प्रभावी ढंग से रिसेप्टर से बंधती है और शरीर में प्रतिक्रिया को उत्तेजित करती है।

A person or animal involved in a contest or conflict, especially in a dramatic context.