That lucky pickpocket? (3)

I believe the answer is:

dip

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'pickpocket?' is the definition.
('dip' can be a synonym of 'pickpocket')

I don't understand the rest of the clue.

(Other definitions for dip that I've seen before include "Sink; thick sauce" , "Depression in a surface" , "Sudden sharp decrease in quantity" , "Pickpocket" , "Lower into water for short swim" .)

I've seen this clue in the Evening Standard.

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