Both etouffee and gumbo start with a roux but they are different How?

Etouffee is an entree; gumbo is a soup

An Etouffee is typically thicker than a gumbo, they can both have the exact same ingredients where the roux used for the gumbo is typically a darker roux and thus it is necessary to use an oil for the higher smoking point. Roux for the Etouffee is typically blond and usually is made with butter, making the dish richer and more of an entree than a stew or soup.