The toothbrush moustache is a style of moustache in which the sides are vertical, often approximating the width of the nose and visually resembling the bristles on a toothbrush. First becoming popular in the United States in the late 19th century, it later spread to Germany and elsewhere. Comedians such as Charlie Chaplin and Oliver Hardy popularized it, reaching its heyday during the interwar years. By the end of World War II, the association with Nazi leader Adolf Hitler made it unfashionable, leading to it being colloquially termed the 'Hitler moustache'.

A toothbrush is an oral hygiene tool used to clean the teeth, gums, and tongue. It consists of a head of tightly clustered bristles, atop of which toothpaste can be applied, mounted on a handle which facilitates the cleaning of hard-to-reach areas of the mouth. They should be used in conjunction with something to clean between the teeth where the bristles of the toothbrush cannot reach - for example floss, tape or interdental brushes.