Cheer is loud -- two letters in a row written about it (8)

I believe the answer is:

embolden

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'cheer' is the definition.
(synonyms)

I cannot understand how the rest of the clue works.

(Other definitions for embolden that I've seen before include "Hearten" , "Inject courage into - me blonde" , "Encourage" , "Make daring" , "To cheer" .)

I've seen this clue in The Telegraph.

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