Shoot that smug fellow to the back of the class! (5)

I believe the answer is:

sprig

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'shoot' is the definition.
(I've seen this in another clue)

I don't understand how the rest of the clue works.

(Other definitions for sprig that I've seen before include "Purloined" , "Youth" , "Stem of holly, for example" , "What may be flowering" , "Young man" .)

I've seen this clue in the Evening Standard.

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