micromortWiktionary 原文/ˈmaɪkrəˌmɔ(r)t/构词拆解micromicro-前缀‘one millionth’mortmort词干‘death’micro-(diminutive) Very small. · (metric units) One millionth.词源说明From micro- (“one millionth”) + mort (“death”).释义名词noun1A unit of risk equivalent to a one-in-a-million probability of death.