Decimetre
The decimetre (SI symbol dm) or decimeter (American spelling) is a unit of length in the metric system, equal to one tenth of a metre (the International System of Units base unit of length), ten centimetres or 3.937 inches. The common non-SI metric unit of volume, the litre, is defined as one cubic decimetre although, from 1901 to 1964, there was a slight difference between the two due to the litre being defined with respect to the kilogram rather than the metre.