All guys round pinball machine, initially excited: American one with flipper (7)

I believe the answer is:

grampus

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'one with flipper' is the definition.
I can't judge whether this definition defines the answer.

'all guys round pinball machine initially excited american' is the wordplay.
'initially' suggests taking the first letters.
'excited' is an anagram indicator.
'american' becomes 'us' (United States).
The first letters of 'all guys round pinball machine' is 'agrpm'.
'agrpm' is an anagram of 'gramp'.
'gramp'+'us'='GRAMPUS'

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(Other definitions for grampus that I've seen before include "huge creature" , "Dolphin - killer whale" , "Killler-whale" , "Killer-whale" , "Good synchronised swimmer" .)

I've seen this clue in The Guardian.

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