Climb on Etna? (5)

I believe the answer is:

mount

I believe this clue is a double definition.

'climb on' is the first definition.
(synonyms)

'etna?' is the second definition.
(etna is a kind of mount)

(Other definitions for mount that I've seen before include "- - Sinai" , "St. Helens, for example" , "Take < a back" , "Produce - horse" , "hill" .)

I've seen this clue in The Telegraph.

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