Stirs octopus, crab slice around (4,2)

I believe the answer is:

arcs up

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'stirs' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'octopus crab slice around' is the wordplay.
'slice' indicates the answer is hidden within the clue.
'around' says the letters should be written in reverse.
'puscra' is hidden in the letters of 'octopus crab'.
'puscra' written backwards gives 'ARCS UP'.

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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