A male sheep knocked over a rodent (4)

I believe the answer is:

mara

'a rodent' is the definition.
(I know that mara is a type of rodent)

'a male sheep knocked over' is the wordplay.
'male sheep' becomes 'ram' (a ram is a male sheep).
'knocked over' shows that the letters should be reversed in order.
'a'+'ram'='aram'
'aram' reversed gives 'MARA'.

I've seen this clue in The Times.

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