What are hoodies called in America?

A hoodie (in some cases it is also spelt hoody and alternatively known as a hooded sweatshirt) is a sweatshirt with a hood. Hoodies often include a muff sewn onto the lower front, and (usually) a drawstring to adjust the hood opening.

The word hood derives from the Anglo-Saxon word hōd, ultimately of the same root as an English hat. The garment's style and form can be traced back to Medieval Europe when the preferred clothing for monks included a hood called a cowl attached to a tunic or robes, and a chaperon or hooded cape was very commonly worn by any outdoors worker

Sweatshirts are also almost exclusively casual attire and hence not as dressy as some sweaters. Sweatshirts may or may not have a hood. A sweatshirt with a hood is now usually referred to as a hoodie, although more formal media still use the term "hooded sweatshirt".