Murdered, as is Christmas turkey? (7)

I believe the answer is:

stuffed

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'murdered as' is the definition.
The definition and answer can be both related to change as well as being past participle verbs.
Perhaps there's an association between them I don't understand?

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for stuffed that I've seen before include "Crammed" , "A . . . . . . . shirt is a pompous man" , "Full of food" .)

I've seen this clue in The Times.

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