Definition

1. Proper noun:
   • International System of Units (SI): A globally accepted, coherent system of measurement units based on seven fundamental quantities: length (meter), mass (kilogram), time (second), electric current (ampere), thermodynamic temperature (kelvin), amount of substance (mole), and luminous intensity (candela). It is the modern form of the metric system.

Usage

• The term "International System" is most commonly used as a shortened form of the full name "International System of Units." It functions as a proper noun referring to this specific scientific and technical standard.
• It is often abbreviated as SI, from the French "Système International d'Unités."

Examples

• Proper noun:
  • All measurements in the physics experiment were recorded using the International System.
  • The International System provides a universal language for science and trade.
  • Converting to the International System simplifies communication between researchers worldwide.

Advanced Usage

• "SI units": This is the most frequent way to refer to the individual units within the system.
  • The newton (N) is an SI unit of force.
• "SI prefixes": Refers to the standard set of prefixes (like kilo-, milli-, micro-) used to denote decimal multiples and submultiples of SI units.
  • A kilometer is 1,000 meters, using the SI prefix 'kilo-'.

Variants and Related Words

• SI (abbreviation): The standard abbreviation for the International System of Units.
• Metric system: A broader term for the decimal-based system of measurement; the International System is its modern, internationally agreed-upon version.
• Système International d'Unités (French): The original French name from which the abbreviation SI is derived.

Synonyms

• SI system
• Modern metric system

Related Phrases

• Base SI units: Refers specifically to the seven fundamental units (meter, kilogram, second, ampere, kelvin, mole, candela) upon which the system is built.
• Derived SI units: Units formed by combining the base units according to algebraic relations (e.g., the watt for power, which is kg·m²/s³).

Noun

1. a complete metric system of units of measurement for scientists; fundamental quantities are length (meter) and mass (kilogram) and time (second) and electric current (ampere) and temperature (kelvin) and amount of matter (mole) and luminous intensity (candela)
   • Today the United States is the only country in the world not totally committed to the Systeme International d'Unites