metrication(n = noun.act) metrification - the act of changing from imperial units of measurement to metric units: meters, grams, seconds;
is a kind of change
Derived form verb metricate₁

   The act or process of converting the standard system of units of a country to those of the metric system; metrification; as, Great Britain has completed its metrification, but the United States still resists complete change. [PJC]