Don't stop swelling, Doctor! (7)

I believe the answer is:

surgeon

I'm a little stuck... Click here to teach me more about this clue!

'doctor' is the definition.
(I know that doctor can be written as surgeon)

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for surgeon that I've seen before include "Sawbones" , "9 practitioner (through keyhole?)" , "incisive person" , "Doctor in operating theatre - RN doctor" , "Medical knife wielder" .)

I've seen this clue in the Sydney Morning Herald.

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