Refuse, sir, or retainer will come back secretly to threaten them with violence (9)

I believe the answer is:

terrorise

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'threaten them with violence' is the definition.
I can't judge whether this defines the answer.

'refuse sir or retainer will come back secretly' is the wordplay.
'secretly' says the answer is hidden in the clue.
'will come back' is a reversal indicator.
'esirorret' is hidden within 'refuse sir or retainer'.
'esirorret' written backwards gives 'TERRORISE'.

'to' acts as a link.

Can you help me to learn more?

(Other definitions for terrorise that I've seen before include "Panic" , "Frighten greatly" , "Spook" , "Frighten or menace like roisterer" , "Oppress by fear" .)

I've seen this clue in The Irish Times.

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