(n)constant-volume process, isometric process, isovolumetric process, isochoric processa thermodynamic process during which the volume of the closed system undergoing such a process remains constant.“In practice, a gas that receives heat in an isochoric process is a constant volume heating and at the same time it is a constant volume pressurization; a gas that looses heat in an isochoric process is a constant volume cooling and at the same time it is a constant volume depressurization.”