The undercut is a hairstyle that was fashionable from the 1910s to the 1940s, predominantly among men, and saw a steadily growing revival in the 1980s before becoming fully fashionable again in the 2010s. Typically, the hair on the top of the head is long and is often parted on either the side or center, while the back and sides are buzzed very short. It is closely related to the curtained hair of the mid-to-late 1990s, although those with undercuts during the 2010s tended to slick back the bangs away from the face.

A regular haircut, in Western fashion, is a men's and boys' hairstyle that has hair long enough to comb on top, a defined or deconstructed side part, and a short, semi-short, medium, long, or extra long back and sides. The style is also known by other names including taper cut, regular taper cut, side-part and standard haircut; as well as short back and sides, business-man cut and professional cut, subject to varying national, regional, and local interpretations of the specific taper for the back and sides.