mass extinction
短语词形变化
mass extinctions
复数
mass extinctions
释义与例句
n.
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1.
A sharp decrease in the total number of species in a relatively short period of time; specifically, a loss of ∼75% of all species on the planet over a geologically interval of less than 3 million years, as a result of a mass extinction event.
可数 不可数 地质