reactivity
/ˌrɪækˈtɪvətɪ/noun
mass noun
1- the state or power of being reactive or the degree to which a thing is reactive反应性, 反应率, 反应度, 反应能力。
1.1
- the extent to which a nuclear reactor deviates from a steady state（核反应堆中核裂变的）反应率。