1. basketball to jump up and force a ball through a basket
2. US informal to defeat decisively ⇒ You are the best. You have slam-dunked everyone in this pool.
3. US informal to push something or someone somewhere with great force ⇒ There was a time when he'd have swooped into your shop, slam-dunked the muffin into his coat pocket, balanced the change on top of your head and been out of there., ⇒ 'How did you get her off?'—'I slam-dunked the security officer.'
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