Completely dark, unlike red carpet at Oscars ceremony? (8)

I believe the answer is:

starless

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'completely dark' is the definition.
'starless' can be an answer for 'dark' (I've seen this in another clue). I'm not sure about the 'completely' bit.

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

Can you help me to learn more?

(Other definitions for starless that I've seen before include "Dark" , "with nobody famous appearing" , "like a low-budget movie?" , "Like The Sky At Night, sometimes" , "Black" .)

I've seen this clue in The Times.

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