Not the sole list (4)

I believe the answer is:

heel

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'list' is the definition.
(both can mean to lean or tilt)

I don't understand the remainder of the clue.

(Other definitions for heel that I've seen before include "Scoundrel - list - shoe part" , "villain" , "Cad,bounder, blackguard" , "A cad and a bounder!" , "I might let down" .)

I've seen this clue in the Evening Standard.

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