Alien escaping from petri dishes running like an insect (9)

I believe the answer is:

spiderish

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'alien escaping from petri dishes running like an insect' is the definition.
I can't tell whether this definition defines the answer.

'alien escaping from petri dishes running' is the wordplay.
'alien' becomes 'et' (extra terrestrial).
'escaping from' suggests deleting specific letters.
'running' indicates an anagram.
'petri'+'dishes'='petridishes'
'petridishes' with 'et' taken out is 'pridishes'.
'pridishes' is an anagram of 'SPIDERISH'.

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I've seen this clue in The Hindu.

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