A tunic is any of several types of garment for the body, usually simple in style, reaching from the shoulders to a length somewhere between the hips and the ankles. The name derives from the Latin tunica, the basic garment worn by both men and women in Ancient Rome, which in turn was based on earlier Greek garments that covered people around their waist.

The tunic or chiton was worn as a shirt or gown by both genders among the ancient Romans. The body garment was loose-fitting for males, usually beginning at the neck and ending above the knee. A woman's garment could be either close fitting or loose, beginning at the neck and extending over a skirt or skirts.

The tunic continued to be the basic garment of the Byzantine Romans of both sexes throughout the medieval period. The upper classes wore other garments atop the basic tunic, such as the dalmatica, a heavier and shorter type of tunic, again, worn by both sexes, or the scaramangion, a riding-coat of Persian origin.

According to wikipedia