Decorate missing central point — that becomes showy (6)

I believe the answer is:

garish

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

I don't understand the rest of the clue.

(Other definitions for garish that I've seen before include "Excessively bright, over-colourful (6)" , "Overly ostentatious" , "Hag, sir, could be gaudy" , "Bright and showy" , "Tastelessly bright" .)

I've seen this clue in The Times.

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