Unusual throttle lacking length (7)

I believe the answer is:

strange

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'unusual' is the definition.
(I know that unusual can be written as strange)

I can't explain the remainder of the clue.

(Other definitions for strange that I've seen before include "Abnormal" , "Eccentric" , "Unusual, odd" , "Out of the ordinary" , "Odd, peculiar" .)

I've seen this clue in The Telegraph.

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