1. The quality of prevailing generally; being widespread
   "he was surprised by the prevalence of optimism about the future"
    
2. A superiority in numbers or amount
   "a prevalence of evidence against the defendant";
   - preponderance
    
3. (epidemiology) the ratio (for a given time period) of the number of occurrences of a disease or event to the number of units at risk in the population
   "The prevalence of diabetes in the adult population was 8.5%"

Derived forms: prevalences

Type of: figure, generality, number, ratio

Encyclopedia: Prevalence