Spanish army guy promoted at a party (7)

I believe the answer is:

soldado

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'spanish army guy' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'promoted at a party' is the wordplay.
'promoted' becomes 'sold'.
'at' says to put letters next to each other.
'party' becomes 'do' (do is a kind of party).
'sold'+'a'+'do'='SOLDADO'

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I've seen this clue in The Independent.

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