Singular bravery seeing off a source of affliction (7)

I believe the answer is:

scourge

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'affliction' is the definition.
(synonyms)

I don't understand the remainder of the clue.

(Other definitions for scourge that I've seen before include "Whip used to inflict punishment" , "big nuisance" , "Affliction - whip" , "Whip - bane" , "Whip, flog" .)

I've seen this clue in The Independent.

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