Centi- is a metric system prefix that denotes one hundredth of the base unit. It is commonly used in scientific and mathematical measurements. However, in everyday language, there are some synonyms that can be used instead of centi-. Some of these synonyms include "hundredth," "per hundred," "percent," and "centesimal." These words can be used interchangeably with centi- in a sentence. For example, a centimeter is the same as saying a hundredth of a meter. Similarly, 20 percent is the same as saying 0.2 or twenty per hundred. Overall, centi- and its synonyms are important in understanding measurements and calculations in various fields.