Envoy from Elizabeth bestowing title on beheaded Scottish queen (8)

I believe the answer is:

emissary

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'envoy' is the definition.
(synonyms)

I don't understand the remainder of the clue.

(Other definitions for emissary that I've seen before include "Government agent" , "Someone sent on a mission" , "I'm sent!" , "Person sent on a diplomatic mission" , "Representative sent on a mission" .)

I've seen this clue in The Guardian.

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