Crossword Genius

Funds to frighten money-spinner (4,3)

Ross

I believe the answer is:

cash cow

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'money-spinner' is the definition.
(synonyms)

'funds to frighten' is the wordplay.
'funds' becomes 'cash' (I've seen this before).
'to frighten' becomes 'cow' (I can't justify this - if you can you should believe this answer much more).
'cash'+'cow'='CASH COW'

Can you help me to learn more?

(Other definitions for cash cow that I've seen before include "Money-spinning business" , "Money-maker" , "producing high market share" , "Product or business making easy money" , "profitable business" .)

I've seen this clue in The Hindu.
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