Tuxedos vs. Suits: What’s the Real Difference When it comes to formal menswear, the tuxedo and the suit occupy distinct, although occasionally overlapping, territories. A tuxedo—also called a dinner jacket—signals black‑tie or white‑tie events and is defined by its satin or grosgrain detailing on the lapels, side stripe, buttons, and often the trouser inseam. The classic tuxedo is traditionally paired with a pleated or...