The term 'force unit' can refer to three different units of measurement: the dyne (4 letters), the newton (6 letters), and the COP (3 letters). The dyne is a unit of force equal to 10 micronewtons, or the amount of force required to accelerate a mass of one gram at a rate of one centimeter per second squared. The newton is the SI unit of force, equal to the amount of force required to accelerate a mass of one kilogram at a rate of one meter per second squared. The COP is a unit of force equal to one hundredth of a newton.