What are jockshorts?

A jockstrap is a kind of undergarment for men intended for athletic use. The garment consists of a waistband and a pouch in front in which the penis and scrotum/testicles are worn, connected under the legs to the waistband in back. Jockstraps typically do not have a seat. The pouch is typically from a highly stretchy, resilient, supportive material since the point to a jockstrap is to give extra support to the genitals during physical activity and thereby reduce or prevent injury.