Period of darkness (5)

I believe the answer is:

night

'period of darkness' is the definition.
(it is dark at night)

This is all the clue.

(Other definitions for night that I've seen before include "Time for turning" , "death" , "Time for bed" , "follow-up to 16 [TWILIGHT]" , "Hours of darkness" .)

I've seen this clue in The Independent, the Sydney Morning Herald, the Evening Standard, The Sun and The Mirror.

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