Hypertension, or high blood pressure, is a condition in which blood-pressure at rest is higher than the body's needs. Because hypertension lacks overt symptoms, high blood pressure can go unnoticed for years.
2. metric-a decimal unit of measurement of the metric system (based on meters and kilograms and seconds); convert all the measurements to metric units; it is easier to work in metric. metric unit.
A kilometre (American spelling: kilometer, symbol: km) is a unit of length equal to 1000 metres (from the Greek words khilia = thousand and metro = count/measure).