Bantamweight is usually a class in boxing for boxers who weigh above 115 pounds (52.163 kg) and up to 118 pounds (53.525 kg). However, in Mixed Martial Arts (MMA) it is 125-136 pounds (56.6 - 61.7 kg). Wrestling also has similar weight classes including bantamweight. The name is derived from bantam chickens.
Read more about Bantamweight: History, Notable Bantamweights, Kickboxing Bantamweight