metric system

See also: Prefixes for Basic Metric Units (table)Prefixes for Basic Metric Units

Multiples
Prefix Abbreviation Power of 10 Equivalent
deka- or deca- da 10¹ ten
hecto- h 10² hundred
kilo- k 10³ thousand
mega- M 10⁶ million
giga- G 10⁹ billion
..... Click the link for more information.

metric system,

system of weights and measuresweights and measures,
units and standards for expressing the amount of some quantity, such as length, capacity, or weight; the science of measurement standards and methods is known as metrology.

Crude systems of weights and measures probably date from prehistoric times.
..... Click the link for more information. planned in France and adopted there in 1799; it has since been adopted by most of the technologically developed countries of the world. It is based on a unit of length, called the metermeter,
abbr. m, fundamental unit of length in the metric system. The meter was originally defined as 1/10,000,000 of the distance between the equator and either pole; however, the original survey was inaccurate and the meter was later defined simply as the distance between two
..... Click the link for more information. (m), and a unit of mass, called the kilogramkilogram,
abbr. kg, fundamental unit of mass in the metric system, defined as the mass of the International Prototype Kilogram, a platinum-iridium cylinder kept at Sèvres, France, near Paris.
..... Click the link for more information. (kg).

The system has changed somewhat since it was first developed; e.g., the definition of the meter has changed, and the unit for mass is different. The meter was originally intended to be 1-10,000,000 of the distance on the earth's surface between the equator and either pole; however, because of errors in the original survey for determining the meter and because of the impracticality of referring to such a standard, the meter was later redefined in terms of the standard prepared and kept at Sèvres, France, near Paris. Long defined as the distance between two scratches on a bar of platinum-iridium alloy, the meter in 1960 was first redefined in terms of an atomic standard. In 1983 the meter was officially redefined as the distance traveled by light in vacuum during 1-299,792,458 of a second.

The original unit of mass, the gramgram,
abbr. g, unit of mass equal to 0.001 kilogram, the basic unit of mass in the metric system. The gram is the unit of mass in the cgs system. It is approximately equal to 0.035 avoirdupois ounce, or 0.0022 pound; a 1-pound mass equals about 453.6 grams.
..... Click the link for more information. , was first defined as the mass of pure water at maximum density that would fill a cube whose edges are each 0.01 m. The unit of mass is now the kilogram, defined as the mass of a platinum-iridium cylinder kept at Sèvres. (A gram is now defined as a mass 1-1,000 kg.) Other metric units can be defined in terms of the meter and the kilogram. For example the are, the unit of area, is equal to the area of a square whose edges are each 10 m long. The liter, the metric unit of volume, is equal to the volume of a cube whose edges are each 1-10 m long.

Fractions and multiples of the metric units are related to each other by powers of 10, allowing conversion from one unit to a multiple of it simply by shifting a decimal point, and avoiding the lengthy arithmetical operations required by the English units of measurement. Standard prefixes (found in the table entitled Prefixes for Basic Metric UnitsPrefixes for Basic Metric Units

Multiples
Prefix Abbreviation Power of 10 Equivalent
deka- or deca- da 10¹ ten
hecto- h 10² hundred
kilo- k 10³ thousand
mega- M 10⁶ million
giga- G 10⁹ billion
..... Click the link for more information. ) have been accepted for designating multiples and fractions of the meter, gram, are, and other units. Thus, 1,000 grams are a kilogram, 100 ares are a hectarehectare
, abbr. ha, unit of area in the metric system, equal to 10,000 sq m, or about 2.47 acres.
..... Click the link for more information. , and 1-100 of a meter is a centimeter.

Several other systems of units based on the metric system have been in wide use. The cgs systemcgs system,
system of units of measurement based on the metric system and having the centimeter of length, the gram of mass, and the second of time as its fundamental units. Other cgs units are the dyne of force and the erg of work or energy.
..... Click the link for more information. is based on the centimeter of length, the gram of mass, and the secondsecond,
abbr. sec or s, fundamental unit of time in all systems of measurement. In practical terms, the second is 1/60 of a minute, 1/3,600 of an hour, or 1/86,400 of a day. Since the length of the day varies, however, the second must be defined in more precise terms.
..... Click the link for more information. of time. The mks systemmks system,
system of units of measurement based on the metric system and having the meter of length, the kilogram of mass, and the second of time as its fundamental units. Other mks units include the newton of force, the joule of work or energy, and the watt of power.
..... Click the link for more information. is based on the meter of length, the kilogram of mass, and the second of time. Units in the mks system are larger than the corresponding cgs units. Electric and magnetic unitselectric and magnetic units,
units used to express the magnitudes of various quantities in electricity and magnetism. Three systems of such units, all based on the metric system, are commonly used.
..... Click the link for more information. have been defined for both of these systems; in fact, two different sets of electric units are defined in the cgs system. The mks system serves as the basis for the International System of UnitsInternational System of Units,
officially called the Système International d'Unités, or SI, system of units adopted by the 11th General Conference on Weights and Measures (1960). It is based on the metric system.
..... Click the link for more information. , a comprehensive system of units for all physical quantities adopted in 1960 by the 11th General Conference on Weights and Measures.

See also decimal systemdecimal system
[Lat.,=of tenths], numeration system based on powers of 10. A number is written as a row of digits, with each position in the row corresponding to a certain power of 10.
..... Click the link for more information. .

Bibliography

See L. V. Judson, Weights and Measures Standards of the United States: A Brief History (1976; U.S. National Bureau of Standards Special Publication 447); K. Alder, The Measure of All Things (2002).

Metric system

A system of units used in scientific work throughout the world and employed in general commercial transactions and engineering applications in most of the developed nations of the world except for the United Kingdom and the United States. The basic units of the metric system define length (meter), mass (kilogram), and time (second).

The chief advantage of the metric system is that it is based on standards that have been accepted by international agreement, and it therefore provides a common basis for all scientific measurements. A second advantage of the metric system lies in the fact that only decimal multiples and submultiples of the fundamental length and mass units and of other derived units are employed. See Physical measurement, Time, Units of measurement

Metric System

(decimal system), a set of units for physical quantities based on the meter as the unit of length. Originally, the metric system also included units of area (the square meter), volume (the cubic meter), and weight (the kilogram; the weight of 1 cubic decimeter of water at 4°C), as well as the liter (for capacity), the are (for the area of plots of land), and the ton (1,000 kg). An important distinctive feature of the metric system was the method of forming multiple and fractional units in decimal ratios; the prefixes kilo-, hecto-, deca-, deci-, centi-, and milli- were adopted to form the names of the derived units.

The metric system was developed in France during the era of the French Revolution. According to a proposal by a commission of leading French scientists (J. Borda, M. Condorcet, P. Laplace, and G. Monge), the meter was adopted as the unit of length and made equal to one ten-millionth of one-quarter of the length of the geographical meridian passing through Paris. This decision resulted from the attempt to provide as a basis for the metric system an easily reproducible “natural” unit of length, which was related to some natural object that was for all practical purposes unchanging. The decree on the introduction of the metric system in France was passed on Apr. 7, 1795. In 1799 a platinum prototype meter was made and approved. The sizes, names, and definitions of the other units of the metric system were chosen in such a way that the system would have no national characteristics and could be adopted by all countries. The metric system became truly international in nature in 1875, when 17 countries, including Russia, signed the Metric Treaty for the provision of international standardization and the improvement of the metric system. The system was authorized for use in Russia (on an optional basis) by a law of June 4, 1899, which was drafted by D. I. Mendeleev, and it was made mandatory by a decree of the Council of People’s Commissars of the RSFSR on Sept. 14, 1918. It was made mandatory for the USSR by a resolution of the Council of People’s Commissars of the USSR on July 21, 1925.

An entire series of special systems of units covering only particular fields of physics and engineering, and also individual subsidiary units, has arisen on the basis of the metric system. The development of science, engineering, and international communications has led to the creation of the International System of Units, a unified system of units based on the metric system that covers all fields of measurement; it has now been made mandatory or is preferred by many countries.

REFERENCES

Isakov, L. D. Na vse vremena, dlia vsekh narodov. Petrograd, 1923.
Burdun, G. D. Edinitsy fizicheskikh velichin. Moscow, 1967.
Shirokov, K. P. “50-letie metricheskoi sistemy v SSSR.” IzmeriteVnaia tekhnika, 1968, no. 9.
Stille, U. Messen und Rechnen in der Physik. Braunschweig, 1961.

metric system

[′me·trik ‚sis·təm] (mechanics) A system of units used in scientific work throughout the world and employed in general commercial transactions and engineering applications; its units of length, time, and mass are the meter, second, and kilogram respectively, or decimal multiples and submultiples thereof.

metric system

any decimal system of units based on the metre. For scientific purposes the Syst?me International d'Unit?s (SI units) is used

metric system

A system of weights and measures that uses the gram, meter and liter as its primary units of weight, distance and capacity. The metric system is used all over the world except in the U.S., Liberia and Myanmar (formerly Burma). See space/time.

COMMON METRIC EQUIVALENTSGrams Pounds Ounces gram .0022 .04 decagram (10) .0220 .35 hectogram (100) .2204 3.5 kilogram (1000) 2.2046 35.3 Liters 1 = 1.06 quarts 3.8 = 1 gallon Meters Feet 1 decameter (10 m) 33 1 hectometer (100 m) 328 1 kilometer (1000 m) 3281 Meters Inches 1 meter 39.37 1 centimeter .3937 1 millimeter .03937 1 micrometer .00003937 1 nanometer .00000003937

metric system

metric

[met´rik] 1. pertaining to measures or measurement.2. having the meter" >meter as a basis.metric system the system of units of measurement that is based on the meter" >meter, gram" >gram, and liter" >liter and in which new units are formed from the basic terms by prefixes denoting multiplication by a power of ten. See also si units" >si units.

system

[sis´tem] 1. a set or series of interconnected or interdependent parts or entities (objects, organs, or organisms) that act together in a common purpose or produce results impossible by action of one alone. 2. an organized set of principles or ideas. adj., adj systemat´ic, system´ic.
The parts of a system can be referred to as its elements or components; the environment of the system is defined as all of the factors that affect the system and are affected by it. A living system is capable of taking in matter, energy, and information from its environment (input), processing them in some way, and returning matter, energy, and information to its environment as output.
An open system is one in which there is an exchange of matter, energy, and information with the environment; in a closed system there is no such exchange. A living system cannot survive without this exchange, but in order to survive it must maintain pattern and organization in the midst of constant change. Control of self-regulation of an open system is achieved by dynamic interactions among its elements or components. The result of self-regulation is referred to as the steady state; that is, a state of equilibrium. homeostasis is an assemblage of organic regulations that act to maintain steady states of a living organism.
A system can be divided hierarchically into subsystems, which can be further subdivided into sub-subsystems and components. A system and its environment could be considered as a unified whole for purposes of study, or a subsystem could be studied as a system. For example, the collection of glands in the endocrine system can be thought of as a system, each endocrine gland could be viewed as a system, or even specific cells of a single gland could be studied as a system. It is also possible to think of the human body as a living system and the endocrine system as a subsystem. The division of a system into a subsystem and its environment is dependent on the perspective chosen by the person studying a particular phenomenon.

Systems, subsystems, and suprasystems. Within the environment there are suprasystems, such as human society, and systems within the suprasystem, such as the educational and industrial systems and the health care delivery system. Within the health care delivery system are subsystems, such as the patient, family members, the nurse, the physician, and allied health care professionals and paraprofessionals.alimentary system digestive system.apothecaries' system see apothecaries' system" >apothecaries' system.autonomic nervous system see autonomic nervous system.avoirdupois system see avoirdupois system" >avoirdupois system.behavioral system in the behavioral system model of nursing, the patterned, repetitive, and purposeful behaviors of an individual.cardiovascular system the heart and blood vessels, by which blood is pumped and circulated through the body; see also circulatory system.CD system (cluster designation) a system for classifying markers" >cell-surface markers expressed by lymphocytes based on a computer analysis of monoclonal antibodies against hla antigens, with antibodies having similar specificity characteristics being grouped together and assigned a number (CD1, CD2, CD3, etc.); these CD numbers are also applied to the specific antigens recognized by the various groups of monoclonal antibodies. See also antigen" >CD antigen.centimeter-gram-second system (CGS) (cgs) a system of measurements in which the units are based on the centimeter as the unit of length, the gram as the unit of mass, and the second as the unit of time.central nervous system see central nervous system.centrencephalic system the neurons in the central core of the brainstem from the thalamus to the medulla oblongata, connecting the hemispheres" >cerebral hemispheres.circulatory system see circulatory system.client system in the general systems framework and theory of goal attainment" >general systems framework and theory of goal attainment, the composite of physiological, psychological, sociocultural, and developmental variables that make up the total person.colloid system (colloidal system) colloid (def. 3).conduction system (conductive system (of heart)) the system of atypical cardiac muscle fibers, comprising the sinoatrial and atrioventricular nodes, internodal tracts, atrioventricular bundle, bundle branch, and terminal ramifications into the Purkinje network.digestive system see digestive system.Emergency Medical Services (EMS) system a comprehensive program designed to provide services to the patient in the prehospital setting. The system is activated when a call is made to the EMS operator, who then dispatches an ambulance to the patient. The patient receives critical interventions and is stabilized at the scene. A communication system allows the health care workers at the scene to contact a trauma center for information regarding further treatment and disposition of the patient, followed by transportation of the patient to the most appropriate facility for treatment.endocrine system the system of ductless glands and other structures that produce internal secretions (hormones) that are released directly into the circulatory system, influencing metabolism and other body processes; see endocrine glands.environmental control system unit" >environmental control unit.expert system a set of computer programs designed to serve as an aid in decision making.extrapyramidal system see extrapyramidal system.gateway system a software interface between an online searcher and one or more search systems, facilitating the use of the system by searchers who are unfamiliar with it, or with online retrieval in general.genitourinary system the organs concerned with production and excretion of urine, together with the reproductive organs. (See Plates.) Called also urogenital system.haversian system a canal" >haversian canal and its concentrically arranged lamellae, constituting the basic unit of structure in compact bone (osteon).

Haversian system: Structures of compact and spongy bone with the central haversian canal surrounded by the lamellae. From Applegate, 2000.health care system see health care system.heterogeneous system a system or structure made up of mechanically separable parts, as an emulsion or suspension.His-Purkinje system the intraventricular conduction system from the bundle of His to the distal Purkinje fibers, which carries the impulse to the ventricles.Home Health Care Classification system see home health care classification system.homogeneous system a system or structure made up of parts that cannot be mechanically separated, as a solution.hypophyseoportal system (hypophysioportal system) (hypothalamo-hypophysial portal system) the venules connecting the hypothalamus with the sinusoidal capillaries of the anterior lobe of the pituitary gland; they carry releasing substances to the pituitary.immune system see immune system.interpersonal system in the general systems framework and theory of goal attainment, two or more individuals interacting in a given situation.lay health system a system comprising an informal referral network and sources of treatment outside the formal biomedical sources of health care; it includes individual consultation and information-seeking through significant others and peers concerning health behaviors, symptoms, and evaluation of treatment before, during, and after consultation with health care professionals.legal system in the omaha system, anything connected with law or its administration; it includes legal aid, attorney, courts, or Child Protective Services (CPS), and many other agencies and officials.limbic system a system of brain structures common to the brains of all mammals, comprising the phylogenetically old cortex (archipallium and paleopallium) and its primarily related nuclei. It is associated with olfaction, autonomic functions, and certain aspects of emotion and behavior.lymphatic system see lymphatic system.lymphoid system the lymphoid tissue of the body, collectively; it consists of primary (or central) lymphoid tissues, the bone marrow, and thymus, and secondary (or peripheral) tissues, the lymph nodes, spleen, and gut-associated lymphoid tissue (tonsils, Peyer's patches).lymphoreticular system the lymphoid and reticuloendothelial systems considered together; see also lymphoreticular disorders.metric system see metric system.mononuclear phagocyte system the group of highly phagocytic cells that have a common origin from stem cells of the bone marrow and develop circulating monocytes and tissue macrophages, which develop from monocytes that have migrated to connective tissue of the liver (kupffer's cells), lung, spleen, and lymph nodes. The term has been proposed to replace reticuloendothelial system, which includes some cells of different origin and does not include all macrophages.nervous system see nervous system.nursing system in the self-care model of nursing, all the actions and interactions of nurses and patients in nursing practice situations; nursing systems fall into three categories: wholly compensatory, partly compensatory, and supportive-educative.Omaha system see omaha system.oxygen delivery system a device that delivers oxygen through the upper airways to the lungs at concentrations above that of ambient air. There are two general types: the fixed performance or high flow type, which can supply all of the needs of a patient for inspired gas at a given fractional inspired oxygen; and the variable performance or low flow type, which cannot supply all of the patient's needs for oxygen and delivers fractional inspired oxygen that varies with ventilatory demand.parasympathetic nervous system see parasympathetic nervous system" >parasympathetic nervous system.peripheral nervous system the portion of the nervous system consisting of the nerves and ganglia outside the brain and spinal cord.personal system in the general systems framework and theory of goal attainment, the unified self, a complex whole that is rational, conscious, and feeling and that sets goals and decides on the means of achieving them.pituitary portal system hypothalamo-hypophysial portal system.portal system an arrangement by which blood collected from one set of capillaries passes through a large vessel or vessels and another set of capillaries before returning to the systemic circulation, as in the pituitary gland (the hypothalamo-hypophysial portal system) or the liver (the hepatic portal circulation).renin-angiotensin-aldosterone system see renin-angiotensin-aldosterone system.respiratory system the group of specialized organs whose specific function is to provide for the transfer of oxygen from the air to the blood and of waste carbon dioxide from the blood to the air. The organs of the system include the nose, the pharynx, the larynx, the trachea, the bronchi, and the lungs. See also respiration and Plates 7 and 8.reticular activating system see reticular activating system.reticuloendothelial system see reticuloendothelial system.safety system see safety system." >safety system.SI system see SI units.skeletal system see skeletal system.social system in the general systems framework and theory of goal attainment, an organized boundary system of social roles, behaviors, and practices developed to maintain balance for growth, development, and performance, which involves an exchange of energy and information between the person and the environment for regulation and control of stressors.support system in the omaha system, the circle of friends, family, and associates that provide love, care, and need gratification; it may include church, school, workplace, or other groupings.sympathetic nervous system see sympathetic nervous system.Unified Medical Language system see unified medical language system.Unified Nursing Language system see unified nursing language system.unit dose system a method of delivery of patient medications directly to the patient care unit. Following review by a nurse, a copy of the physician's original order is sent to the pharmacy, where the pharmacist reviews it again. The pharmacist then fills the order and delivers the medication to the patient care unit, usually in a 24-hour supply. Each patient has an individual supply of medications prepared and labeled by the pharmacist.urinary system the system formed in the body by the kidneys, ureters, urinary bladder, and urethra, the organs concerned in the production and excretion of urine.urogenital system genitourinary system.vascular system circulatory system.vasomotor system the part of the nervous system that controls the caliber of the blood vessels.

met·ric sys·tem

a system of weights and measures, universal for scientific use, based upon the meter, which was originally intended to be one ten-millionth of a quadrant of the earth's meridian and now is based on the length that light travels in a vacuum in a given period of time (see meter). Prefixes of the meter (and other standards) reflect either fractions or multiples of the meter and are identical to the International System of Units (q.v.). The unit of weight is the gram, which is the weight of one cubic centimeter of water, equivalent to 15.432358 grains. The unit of volume is the liter or one cubic decimeter, equal to 1.056688 U.S. liquid quarts; a cubic centimeter is about 16.23073 U.S. minims.

met·ric sys·tem

(met'rik sis'tĕm) A system of weights and measures, universal for scientific use, based on the meter, the gram, and the liter.

met·ric sys·tem

(met'rik sis'tĕm) A system of weights and measures, universal for scientific use, based on the meter, the gram, and the liter.

metric system

metric system

metric system

met′ric sys`tem

metric system

metric system

metric system

metric system,

Bibliography

Metric system

Metric System

REFERENCES

metric system

metric system

metric system

metric system

metric

system

met·ric sys·tem

met·ric sys·tem

met·ric sys·tem

metric system

Words related to metric system

noun a decimal system of weights and measures based on the meter and the kilogram and the second

Related Words