diurnation

noun

di·​ur·​na·​tion

ˌdī(ˌ)ərˈnāshən

plural -s

1

: the habit of sleeping or being quiescent by day

the diurnation of bats

2

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

Word History

Etymology

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

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