Opening, not closing* (4)

I believe the answer is:

star

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'opening not closing' is the definition.
I can't judge whether this definition defines the answer.

'opening not closing' is the wordplay.
'opening' becomes 'start' (I've seen this before).
'not closing' means to remove the last letter.
'start' with its final letter taken off is 'STAR'.

Can you help me to learn more?

(Other definitions for star that I've seen before include "Glamorous celebrity" , "Brilliant person" , "Possible Christmas tree topper?" , "Big name" , "Eg, Betelgeuse" .)

I've seen this clue in The Telegraph.

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