Sweater with a hood that is pulled up over the head, especially one worn by students or gang members. Also called a skullcap. Hoodies have become very popular in recent years. The name "hoodie" was first used by American college students in the mid-1960s to describe a sweater with a hood that was pulled up over the head. Today, a hoodie is defined as a sweatshirt with a zipper or buttoned flap at the neckline. Although they are now commonly worn by adults, hoodies originally were designed for use by children. They can be any color, but most are black, gray, or white. The word "hoodie" is derived from the colloquial English language phrase "to put one's hat on." The expression came about because students would wear their school caps while wearing their hoodies. Since then, it has become common practice for people to wear hats when they go out in the cold. Hoodies are now so popular that there are many different brands and styles. There are several reasons why people choose hoodies over other types of clothing. First, they are easy to put on.