Scoundrels against Her Majesty - one swears (6)

I believe the answer is:

curser

'one swears' is the definition.

'scoundrels against her majesty' is the wordplay.
'scoundrels' becomes 'curs'.
'against' means one lot of letters go next to another.
'her majesty' becomes 'er' (Elizabeth Regina).
'curs'+'er'='CURSER'

(Another definition for curser that I've seen is " I swear".)

I've seen this clue in The Telegraph.

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