die-off

[ dahy-awf, -of ]
/ ˈdaɪˌɔf, -ˌɒf /

noun

a sudden, natural perishing of large numbers of a species, population, or community.

Origin of die-off

First recorded in 1935–40; noun use of verb phrase die off
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Science definitions for die-off

die-off

[ dīôf′ ]

A sudden, severe decline in a population or community of organisms as a result of natural causes. Local die-offs can be caused by such factors as an unusual or extreme weather pattern, an outbreak of disease, or toxic algal blooms in a body of water. Widespread or global die-offs in which a species or group of species becomes extinct are generally associated with rapid climate change or other large-scale environmental dislocations.
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