1. The characteristic of being exhilarating, tending to upset the mind or senses
   "How a mere convention gathering could generate such a shift in regard to an issue like abortion reveals something of the headiness in which many of the gathered were luxuriating"
    
2. The characteristic of being intoxicating or stupefying
   "Wine novices intimidated by the headiness of Napa and Sonoma will feel comfortable at nearly every Oregon winery"
    
3. The quality of being intoxicating or exhilarating
   "The headiness of the wine went straight to her head"
    
4. The quality of being rash or impetuous
   "His headiness in making decisions often led to problems"

Type of: ambiance, ambience, atmosphere, intensity, intensiveness