* Depressed: This is the most direct opposite in terms of emotional state.
* Dull: This describes a lack of energy and excitement, the opposite of exuberant's vibrancy.
* Subdued: This implies a restrained and quiet demeanor, the opposite of exuberant's outward enthusiasm.
* Reserved: This describes someone who is quiet and not easily expressive, contrasting with exuberant's openness.
* Lackadaisical: This suggests a lack of enthusiasm and effort, the opposite of exuberant's zeal.
* Melancholy: This describes a state of sadness and gloom, contrasting with exuberant's joyfulness.
The best opposite word will depend on the specific situation and the nuance you want to convey.