The Latin word caestus (plural: caestūs) is derived from verb caedere, meaning "to strike". It is unrelated to the similar noun cestus (plural: cestī), that refers to a kind of belt worn by women in Ancient Greece.
The first version of a battle cestus was a series of leather thongs that were tied over the hand. Greeks used them in their hand-to-hand competitions, where only knock out mattered. Romans modified the construction by adding metal parts, including spikes, studs, and iron plates. Variants of this weapon include the myrmex or "limb-piercer", and the originally Greek sphairai, thin leather thongs with cutting blades.
Cestus were frequently used in Roman gladiatorial bouts, where otherwise unarmed combatants - mostly slaves - fought to the death. This form of boxing became increasingly bloody until the cestus was officially banned in the first century BC. Hand-to-hand fighting was banned in AD 393. The most famous depiction of the cestus in sculpture is The Boxer of Quirinal, in Rome. The sitting figure is wearing cestus on his hands.