请输入您要查询的英文单词：
单词
ˌcritical ˈmass
释义
ˌcritical ˈmass
NOUN
1
singular/U
the smallest number of people or things needed to make something happen （使某事发生所需的）最少数量的人（或物）
2
C/U
science
the smallest amount of a substance needed to cause a nuclear reaction 临界质量