What is Knock Yourself Out?
1.
Equivalent to "Go for it"
"Can I have a piece of your burrito?"
"Knock yourself out."
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2.
A term for: Do whatever the hell you want, it doesn't bother me.
"dad, can i go to the park?"
"Can you get there yourself?"
"Yeah"
"well then, knock yourself out."
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3.
Same as "go for it" or "go nuts".
If you really dont care at all about a person doing/taking something you say "knock yourself out" as in to do/eat until you pass out (if you really want to).
Same as "go for it" or "go nuts".
Person 1: "Hey man, can I have some beer?"
Person 2: "Yeah, Knock yourself out"
4.
to work hard to achieve something, usually implying success
Wow, Mary! This is a great party. You really knocked yourself out.
It seems every time you give a party you really knock yourself out.
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