In the video Bernice Bobs Her Hair what does bob mean?

In this context, "bob" refers to a particular hairstyle that was popular in the early 20th century. A bob typically involves hair that is cut short, around the chin or jawline, with a blunt or straight edge. It was a significant departure from the long, elaborate hairstyles that were in fashion at the time and became a symbol of modernity and liberation for women.