incidence

名词 incidence:

1. the relative frequency of occurrence of something
   同义词：relative incidence
2. the striking of a light beam on a surface

1. The incidence of cases of rape have increase over the last year.
   强奸案的发案率在去年有所增加。
2. The rate of incidence of a disease.
   发病率发生疾病的概率

in.ci.dence

n.（名词）
The act or an instance of happening; occurrence:
发生，出现：发生的行为或事件；出现：
例句：
did not expect criticism and was surprised by its incidence.
受到未预料的批评而感到吃惊

Extent or frequency of occurrence:
发生频率：出现的范围、程度或频率：
例句：
a high incidence of malaria in the tropics.
热带地区疟疾的高发率

Physics
【物理学】
The arrival of radiation or a projectile at a surface.
入射：辐射或投影到某一表面
Angle of incidence.
入射角