METRIC SYSTEM

the system of weights and measures used in most countries in the European Union which is replacing the imperial system in Britain. The metric system is sometimes also called the International System or Système International and the units of measurement are called SI units . Measurements of length, weight and volume are each derived from a single base unit, the metre , the gram and the litre . Other units of measurement are 10, 100 or 1 000 times smaller or larger than these. Some metric units of measure are spelt differently in British and American English: words ending in -metre and -litre in British English end in -meter and -liter in American English.