Yeah nah is a very non committal way of saying ânoâ. The âyeahâ represents that the person has heard you, and the ânahâ shows that they are replying with a negative or disapproving response. Not to be confused with Nah yeah.
Example: He asked if I wanted to go to pighunting with him on the weekend for our first date, it was a kind offer but I was like yeah nah.