Pick up what hasn’t been dropped? (5)

I believe the answer is:

catch

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'pick up' is the definition.
(I know that pick up can be written as catch)

I can't explain the remainder of the clue.

(Other definitions for catch that I've seen before include "Fly in the ointment" , "Fastener on door or window" , "Getting round" , "Intercept and hold" , "Trap (a batsman?)" .)

I've seen this clue in The Independent.

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