Note: in AM, use 'self-defense'
1.
Self-defence is the use of force to protect yourself against someone who is attacking you.
Richards claimed he acted in self-defence after Pagett opened fire on him during a siege.
...courses in karate or some other means of self-defence.
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2.
Self-defence is the action of protecting yourself against something bad.
Jokes can be a form of self-defence.
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