Swift, Drake or Eminem? (5)

I believe the answer is:

rapid

I'm a little stuck... Click here to teach me more about this clue!

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

I cannot understand how the rest of the clue works.

(Other definitions for rapid that I've seen before include "Happening at great speed" , "Flying" , "Fast, speedy" , "moving fast" , "Quickly accomplished" .)

I've seen this clue in the Sydney Morning Herald.

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