A centigram is a unit of mass in the metric system. It is equal to one hundredth of a gram, or 10 milligrams. The prefix ‘centi-‘ means one hundredth, so a centigram is literally one hundredth of a gram. This unit is not commonly used in everyday measurements but can be found in scientific contexts where precise measurements are required. For example, in chemistry or pharmacology, small quantities of substances might be measured in centigrams.