n'ombre
A big, rude way to tell someone they're full of hot air. Like when someone says they're a superhero and you say 'N'ombre!' because they're not.
He said he's a superhero. I said, 'N'ombre? You can't even jump over a couch.'
She said she can sing like Taylor Swift. I said, 'N'ombre? You can't even hit a note.'
He said he can run a mile in 30 seconds. I said, 'N'ombre? You can't even run a minute.'