damp off

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Damping off

Verb

damp off (third-person singular simple present damps off, present participle damping off, simple past and past participle damped off)

(intransitive) Of plants: to decay and perish through excessive moisture.
- 1991, Complete Guide to Gardening and Landscaping, page 213:
  Sweet alyssum seedlings are particularly prone to damping off, so do not overmoisten the soil.