A belly chain is a physical restraint

Physical restraint

Physical restraint refers to the practice of rendering people harmless, helpless or keeping them in captivity by means such as handcuffs, fetters, straitjackets, ropes, straps, or other forms of physical restraint...

 worn by prisoners, consisting of a chain

Chain

A chain is a sequence of connected links.Chain may also refer to:Chain may refer to:* Necklace - a jewelry which is worn around the neck* Mail , a type of armor made of interlocking chain links...

 around the waist

Waist

The waist is the part of the abdomen between the rib cage and hips. On proportionate people, the waist is the narrowest part of the torso....

, to which the prisoner's hands may be chained or cuffed

Handcuffs

Handcuffs are restraint devices designed to secure an individual's wrists close together. They comprise two parts, linked together by a chain, a hinge, or rigid bar. Each half has a rotating arm which engages with a ratchet that prevents it from being opened once closed around a person's wrist...

. Sometimes the ankles are also connected by means of longer chains.

Such restraints are often used in the United States in courtroom

Courtroom

A courtroom is the actual enclosed space in which a judge regularly holds court.The schedule of official court proceedings is called a docket; the term is also synonymous with a court's caseload as a whole.-Courtroom design:-United States:...

s, or for transporting prisoners

Prisoner transport

Prisoner transport describes the transportation of prisoners by land, air and water. It is performed by law enforcement agencies and their armed agents or officers. Handcuffs are often the minimum restraint, however the additional precaution of leg irons is more often taken, particularly if the...

, or in other public situations as a safeguard against escape.