noun di·ur·na·tion \ˌdī(ˌ)ərˈnāshən\

Definition of diurnation



  1. 1 :  the habit of sleeping or being quiescent by day the diurnation of bats

  2. 2 :  a daily recurrent fluctuation in an ecological community (as the vertical movement of plankton)

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Origin and Etymology of diurnation

Latin diurnus of the day, daily + English -ation (as in hibernation) — more at journal

Seen and Heard

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a rounded knoll or a ridge of ice

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