Crossword Genius

Take off the charge for tax relief (9)

Ross

I believe the answer is:

deduction

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'tax relief' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Maybe there's a link between them I don't understand?

'take off the charge' is the wordplay.
'take off' becomes 'deduct' (synonyms).
'the charge' becomes 'ion' (an ion is a charged particle).
'deduct'+'ion'='DEDUCTION'

'for' acts as a link.

Can you help me to learn more?

(Other definitions for deduction that I've seen before include "Taking off" , "What's lost" , "what Holmes made" , "corollary" , "Removal; finding" .)

I've seen this clue in the Sydney Morning Herald.
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