Denier is a unit for measuring of the relative thickness of fibres in a fabric. The higher the denier, the thicker the fiber. One denier is defined as the thickness of a yarn that has a mass of one gram per 9000 meters. The unit is now mostly obsolete.


A denier is a type of French coin created by Charlemagne. The livre (pound -- both monetary and unit of weight) was worth 240 deniers. The name denier is derived from the name of the Roman coin the denarius.

See also: denar and dinar.