A Decimeter is a unit of measurement. It belongs to the metric system. It equals one tenth of a meter which is the current SI unit of Length. Decimeter is denoted by the symbol dm.
One Decimeter is approximately equal to ten centimeters. And a hundred centimeter make one meter. Also one decimeter is equal to 100 millimeter.
Since 1 dm equals 10 cm so half of decimeter will be 5 cm.