Dark new frameless spectacles (5)

I believe the answer is:

night

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'dark' is the definition.
(it's dark at nighttime)

I don't understand how the rest of the clue works.

(Other definitions for night that I've seen before include "Ignorance" , "''Twas the ... before Christmas, when all through the house / Not a creature was stirring, not even a mouse''" , "follow-up to 16 [TWILIGHT]" , "For most, the time for sleep" , "From dusk until dawn" .)

I've seen this clue in The Independent.

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