Adorns parts of vessels (5)

I believe the answer is:

decks

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'adorns' is the definition.
(decking is a kind of adorning)

I cannot understand how the rest of the clue works.

(Other definitions for decks that I've seen before include "Packs of cards (US)" , "Embellishes" , "Platforms on a vessel" , "Sets of cards" , "Packs of playing cards" .)

I've seen this clue in the Evening Standard.

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