Small weight for a big cat (5)

I believe the answer is:

ounce

I believe this clue is a double definition.

'small weight' is the first definition.
(I've seen this in another clue)

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

'for' is the link.

(Other definitions for ounce that I've seen before include "One cat" , "Atom" , "A light weight - feline" , "Small unit of weight" , "Enough to tip the scales" .)

I've seen this clue in The Guardian.

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