Hold sheriff's men aboard ship (7)

I believe the answer is:

possess

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'hold' is the definition.
(I've seen this in another clue)

'sheriff's men aboard ship' is the wordplay.
'sheriff's men' becomes 'posse' (I've seen this before).
'aboard ship' becomes 'ss' (prefix in ship names eg SS Great Britain. I am not sure about the 'aboard' bit.).
'posse'+'ss'='POSSESS'

Can you help me to learn more?

(Other definitions for possess that I've seen before include "Have and hold" , "Have - control" , "Own, keep" , "Consume" , "influence" .)

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

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