Dressing Like a Grownup
Notched (American English): this lapel is sewn to the collar at an angle, creating a step effect. This is the standard on single breasted suits, and is used on nearly all suit jackets, blazers, and sports jackets. The size of the notch can vary, and a small notch is called fishmouth
Peaked (American English) or Pointed (British English): this lapel is the most formal, featured on double-breasted jackets, and is now always worn with all formal coats such as a tailcoat or morning coat, and also commonly with a dinner jacket (both single and double breasted). In the late 1920s and 1930s, a design considered very stylish was the single breasted peaked lapel jacket, a feature carried into day clothing by the increasing popularity of the peaked dinner jacket. This has gone in and out of vogue periodically, made popular once again during the 1970s by designers such as Armani, and is still a recognized alternative. The ability to properly cut peak lapels on a single-breasted suit is one of the most challenging tailoring tasks, even for very experienced tailors
Shawl or Roll: this lapel is a continuous curve and it is now most common on the dinner jacket (tuxedo). This lapel was originally seen on the Victorian smoking jacket- Additional Features