Gee — a right baddy! (9)

I believe the answer is:

garrotter

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'gee a right baddy' is the definition.
I can't tell whether this defines the answer.

'gee a right baddy' is the wordplay.
'gee' becomes 'g' (synonyms).
'a right' becomes 'ar' (I've seen this in other clues).
'baddy' becomes 'rotter' (a rotten person).
'g'+'ar'+'rotter'='GARROTTER'

Can you help me to learn more?

(Other definitions for garrotter that I've seen before include "Killer" , "Executioner" .)

I've seen this clue in The Times.

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