Big cat, lion, with a bit of rot in foot (7)

I believe the answer is:

leopard

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'big cat' is the definition.
(leopard is a kind of big cat)

'lion with a bit of rot in foot' is the wordplay.
'lion' becomes 'leo' (I have seen 'Zodiacal lion ' mean 'leo' so perhaps 'lion' could also mean 'leo').
'with' indicates putting letters inside.
'a bit of' suggests taking the first letters.
'in foot' becomes 'pad' (padding is a kind of footing. I am not sure about the 'in' bit.**).
The first letter of 'rot' is 'r'.
'r' put within 'pad' is 'pard'.
'leo'+'pard'='LEOPARD'

Can you help me to learn more?

(Other definitions for leopard that I've seen before include "The cat that does not change its spots" , "Spotted animal" , "Powerful cat" , "Animal -- per load (anag)" , "Large spotted cat" .)

I've seen this clue in The Telegraph.

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