Refuse to deal with opener in the past (7)

I believe the answer is:

boycott

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'refuse to deal with' is the definition.
(I've seen this before)

I don't understand the rest of the clue.

(Other definitions for boycott that I've seen before include "Ostracise" , "Refuse to deal with (someone) as a protest" , "Refuse to trade with" , "Refuse to do business with" , "Refuse to deal with - outlaw" .)

I've seen this clue in The Hindu.

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