What does 'my bad' mean?

What it means: "My fault" or "I made a mistake." It's a casual, low-key admission of error without a full apology.

Why natives say this: "My bad" emerged from American basketball slang in the 1970s-80s and went mainstream in the 1990s. It's shorter and less formal than "I apologise" or "that was my fault." The tone is light — it acknowledges the mistake without making a big deal of it.

When to use it: With friends, colleagues you know well, or in casual situations. Not appropriate in a formal apology or professional email — use "I apologise" or "that was my mistake" instead.

Register: Informal. Universally understood in American English; well-known in British English though less commonly said.

Tags: American English, apology, informal, slang