What does "knock yourself out" mean?
Two and a half men. A woman said:
"I'm gonna take this seat cushion, okay?"
Charlie answered:
"Knock yourself out."

What does that exactly mean?

Question

What does "knock yourself out" mean?
Two and a half men. A woman said:
"I'm gonna take this seat cushion, okay?"
Charlie answered:
"Knock yourself out."

What does that exactly mean?

Answer

"knock yourself out" = go for it

Answer

it means she is doing a great effort
she made herself tired or exhausted herself