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 cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for dip that I've seen before include "Dunk" , "Immerse briefly in liquid" , "Pickpocket" , "Depression in a surface" , "Thick sauce; brief swim" .)

I've seen this clue in the Evening Standard.

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