Large number Hun eliminated, inspiring a terror (5)

I believe the answer is:

dread

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'terror' is the definition.
(both can mean a feeling of angst)

I cannot understand how the rest of the clue works.

(Other definitions for dread that I've seen before include "Fear - dire" , "Be afraid of - anxiety" , "Show horror" , "Trepidation" , "Deep fear" .)

I've seen this clue in The Times.

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