Sell deathtrap, occasionally the cause of bitter feud (8)

I believe the answer is:

vendetta

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'bitter feud' is the definition.
(I've seen this before)

'sell deathtrap occasionally' is the wordplay.
'sell' becomes 'vend' (vending is a kind of selling).
'occasionally' means one should take alternating letters.
The alternate letters of 'deathtrap' are 'etta'.
'vend'+'etta'='VENDETTA'

'the cause of' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.

Can you help me to learn more?

(Other definitions for vendetta that I've seen before include "ongoing row" , "A prolonged feud, associated with Sicily" , "Private feud" , "Violent quarrel" , "Long-running quarrel" .)

I've seen this clue in The Telegraph.

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