Conceal handily (4)

I believe the answer is:

palm

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

I don't understand the rest of the clue.

(Other definitions for palm that I've seen before include "Leaf in part of the hand?" , "Tropical tree with large leaves" , "Flat part of the hand" , "may need greasing" , "Date-tree" .)

I've seen this clue in the Evening Standard.

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