incidence

in·ci·dence

noun \ˈin(t)-səd-ən(t)s, -sə-ˌden(t)s\

Definition of INCIDENCE

1

a : angle of incidence b : the arrival of something (as a ray of light) at a surface

2

a : an act or the fact or manner of occurring or affecting <diseases of domestic incidence—Science> b : rate of occurrence or influence; especially : the rate of occurrence of new cases of a particular disease in a population being studied—compare prevalence