Major Campbell some killer? (4)

I believe the answer is:

orca

'killer?' is the definition.
('orca' can be a synonym of 'killer')

'major campbell some' is the wordplay.
'some' indicates the answer is hidden within the clue.
'ORCA' is hidden within 'major campbell'.

(Other definitions for orca that I've seen before include "ship" , "Killer at sea" , "Large predator" , "Cor! a killer whale" , "Killer in deep" .)

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

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