In reguard to saying something is like 'Dayum' or extremely nice looking etc... Or, once you've accomplished something it follows after the completion to show emphasis on you being able to do so.
Guy1: "Hey did you see that girl?"
Guy2: "Yeah, man, she was like Tah dowww!"

Guy1: "Man I can't get this shit to work"
Guy2: "Lemme try n help you out....*helps him out*....*fixes it*..... Tah Dowww mo' fuckaaa!"
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