Pours ice in jars, having a harmful effect (10)

I believe the answer is:

pernicious

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'having a harmful effect' is the definition.
I can't tell whether this definition defines the answer.

'pours ice in jars' is the wordplay.
'jars' indicates anagramming the letters (the letters must be shocked or jarred).
'pours'+'ice'+'in'='poursicein'
'poursicein' with letters rearranged gives 'PERNICIOUS'.

Can you help me to learn more?

(Another definition for pernicious that I've seen is " Destructive and harmful".)

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

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