Stunned European given the sack (8)

I believe the answer is:

poleaxed

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'stunned' is the definition.
The definition and answer can be both to do with contact as well as being past participle verbs.
Perhaps they are linked in a way I don't understand?

'european given the sack' is the wordplay.
'european' becomes 'pole' (someone from Poland).
'given the sack' becomes 'axed' (I've seen this in another clue).
'pole'+'axed'='POLEAXED'

Can you help me to learn more?

(Other definitions for poleaxed that I've seen before include "Greatly shocked" , "Felled" .)

I've seen this clue in The Times.

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