Descriptive of the sky in a twinkling? (7)

I believe the answer is:

starlit

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'twinkling?' is the definition.
Both the answer and definition are adjectives. Perhaps there's an association between them I don't understand?

I cannot understand how the rest of the clue works.

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(Other definitions for starlit that I've seen before include "Illuminated by the night sky" , "romantic setting" , "Illuminated at night (including a newspaper)" .)

I've seen this clue in The Irish Independent.

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