The term 'PREFIX WITH METRIC' refers to four prefixes that are commonly used in the metric system. ECONO is a five-letter prefix meaning 'ECONOMIC, ' GEO is a three-letter prefix meaning 'geographical, ' ISO is a three-letter prefix meaning 'EQUAL, ' and OPTO is a four-letter prefix meaning 'OPTICAL.' These prefixes are used to denote various measurements in the metric system, such as ECONOMIC cost, geographical distance, EQUAL parts, and OPTICAL power.