A decimeter is a unit of measurement. It is denoted by the symbol 'dm'. Decimeter is used to measure length. Deci is related to ten. Thus, decimeter is equal to ten centimeters. A hundred centimeters makes one meter. Thus, a centimeter is a one hundred part of a meter. So, a decimeter (10 centimeters) is one-tenth part of a meter.
According to international standards of measurement, one decimeter is equal to hundred millimeters. One centimeter equals ten millimeters. Hence, ten centimeters will be equal to hundred millimeters which is a decimeter. International system of units also states a decimeter to be equal to 100×10−6 km. One thousand meters constitute a kilometer. Thus, meter is a thousandth part of a kilometer. Hence, a decimeter will be 0.0001 part of a kilometer. One decimeter is also accepted as 1×109 Armstrong.