Ferrets let out in mini jumpers (7)

I believe the answer is:

rootles

'ferrets' is the definition.
(rootle can mean to ferret around)

'let out in mini jumpers' is the wordplay.
'out' is an anagram indicator (out can mean wrong or inaccurate).
'in' means one lot of letters goes inside another.
'mini jumpers' becomes 'roos' (short for 'kangaroos', animals that jump).
'let' is an anagram of 'tle'.
'tle' going into 'roos' is 'ROOTLES'.

I've seen this clue in The Guardian.

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