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Brace of flightless birds, fast but not hot (8)

Ross

I believe the answer is:

reassure

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'brace' is the definition.
(thesaurus)

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(Other definitions for reassure that I've seen before include "Take away a person's doubts or fears" , "Comfort, convince again" , "Give confidence to" , "Buoy up" , "give encouragement" .)

I've seen this clue in The Telegraph.
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