Bending fine classical laws, one's charged (7)

I believe the answer is:

flexion

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'bending' is the definition.
(I know that flexion is a type of bending)

'fine classical laws one's charged' is the wordplay.
'fine classical laws one' becomes 'flex' (I can't justify this - if you can you should give a lot more credence to this answer).
'charged' becomes 'ion' (I've seen this in other clues).
'flex'+'ion'='FLEXION'

Can you help me to learn more?

I've seen this clue in The Independent.

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