quality factor
noun
1- Physics a parameter of an oscillatory system or device, such as a laser, representing the degree to which it is undamped and hence expressing the relationship between stored energy and energy dissipation【物理】品质因数。
1.1
- a figure expressing the ability of ionizing radiation to cause biological damage, relative to a standard dose of X-rays（致电离辐射造成生物伤害力的）标准指数。