A way of admitting a mistake, and apologizing for that mistake, without actually apologizing. The best definition I ever read of this, now paraphrased:

"I did something bad, and I recognize that I did something bad, but there is nothing that can be done for it now, and there is technically no reason to apologize for that error, so let's just assume that I won't do it again, get over it, and move on with our lives."

Ruder than apologizing, but with the same meaning: a flippant apology.
"You just spilled your beer on my term paper!!"
"Er... my bad."
by Lita August 17, 2004
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A way of appologizing when you don't reallly care about the situation. Kind of like saying whatever.
Teacher: Joe, stop texting
Joe: My bad
by a keyboard December 12, 2009
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Incredibly annoying phrase which people use when they do something stupid or wrong
Kim: You just pulled my ex boyfriend
Lucie: My bad
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My bad. I did not mean to step on your toe.
by Light Joker December 19, 2004
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Moronic phrase used by pretentious, clueless twats to acknowledge they have made an error
I forgot to remove the safety catch before putting the gun against my own dumb-ass head and pulling the trigger. My bad
by Mike Tench November 16, 2010
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This phrase actually came from bad spelling and the internet. Lazy spellers who couldn't be bothered with an apostrophe said:

"your bad" instead of "you're bad", the latter being correct (a contraction for YOU ARE BAD), but the former being more common.

The proper response to "your bad" is OH, it's MY BAD? The "bad" being possessive.
I ditched school today. My bad." from the original "oh, you ditched today? Your bad.
by badnursey January 14, 2011
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a phrase to be used when you have made a mistake and suddenly realise your error.Some say its Widely used in Britian
"Have you used my toothbrush?"
"No bitch, why?"
"Coz its got limescale on it, innit?"
"NO! I ain't used your skanky tootbrush."
"My bad dawg, my bad."
by roger wilson March 6, 2008
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