Ban one of ex-husband’s family? (6)

I believe the answer is:

outlaw

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'ban' is the definition.
(I know that ban is a more specific form of outlaw)

I don't understand the remainder of the clue.

Can you help me to learn more?

(Other definitions for outlaw that I've seen before include "Ban, make illegal" , "Josey Wales was one" , "Criminal, bandit" , "Nonconformist" , "Declare illegal" .)

I've seen this clue in The Times.

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