* Mild: This is a general antonym, suggesting a lack of intensity or forcefulness.
* Calm: This implies a state of peace and composure, the opposite of passionate or forceful.
* Subdued: This suggests a lack of energy or enthusiasm, contrasting with the passionate energy of something vehement.
* Passive: This emphasizes a lack of active participation or engagement, the opposite of forceful action or expression.
* Indifferent: This implies a lack of interest or concern, contrasting with the strong feelings associated with vehemence.
* Tepid: This suggests a lack of enthusiasm or excitement, the opposite of intense passion.
* Moderate: This implies a balanced and controlled approach, contrasting with the extreme nature of vehemence.
The best antonym will depend on the specific situation and the nuance you want to convey.