Volcano dormant, evidently has packed up! (4)

I believe the answer is:

etna

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'volcano' is the definition.
(Mount Etna)

I cannot understand how the rest of the clue works.

(Other definitions for etna that I've seen before include "source of fumes?" , "Highest active volcano in Europe" , "a mount hotly tipped when it runs" , "Volcano in Sicily, quite neat" , "hole in the crust" .)

I've seen this clue in The Times.

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