Can charge a large amount (10)

I believe the answer is:

bucketload

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'a large amount' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'can charge' is the wordplay.
'can' becomes 'bucket' (I can't explain this - if you can you should give a lot more credence to this answer).
'charge' becomes 'load' (synonyms).
'bucket'+'load'='BUCKETLOAD'

Can you help me to learn more?

(Other definitions for bucketload that I've seen before include "Very large amount" , "great deal" .)

I've seen this clue in The Guardian.

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