It shines when the sun ain’t out! (5)

I believe the answer is:

satin

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'it shines when' is the definition.
The definition suggests a singular noun which matches the answer.

'sun ain't out' is the wordplay.
'sun' becomes 's' (abbreviation).
'out' indicates an anagram (out can mean wrong or inaccurate).
'aint' with letters rearranged gives 'atin'.
's'+'atin'='SATIN'

'the' is the link.

Can you help me to learn more?

(Other definitions for satin that I've seen before include "Saint (anag.)" , "Silk fabric" , "Stain on shiny fabric" , "Stain on shiny cloth" , "Stain on silky cloth" .)

I've seen this clue in the Evening Standard.

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