Any hairstyle for medium-length hair where the hair is cut along a circular line around the head, letting it cover the ears and hang above the shoulders
A bob cut, also known as a bob, is a short to medium length haircut, in which the hair is typically cut straight around the head at approximately jaw level, and no longer than shoulder-length, often with a fringe at the front. The standard bob cut exposes the back of the neck and keeps all of the hair well above the shoulders. Wikipedia