Realists dismissing lies in The Sun (4)

I believe the answer is:

star

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'the sun' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for star that I've seen before include "Possible Christmas tree topper?" , "Five-pointed celestial body" , "Famous entertainer" , "top player" , "Twinkling celestial body" .)

I've seen this clue in the Irish Times.

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