What is the meaning of metric?

noun

• A function of a topological space that gives, for any two points in the space, a value equal to the distance between them.
  • synonyms: metric function
• A decimal unit of measurement of the metric system (based on meters and kilograms and seconds. )
  • usage: "convert all the measurements to metric units"; "it is easier to work in metric"
  • synonyms: metric unit
• A system of related measures that facilitates the quantification of some particular characteristic.
  • synonyms: system of measurement

adjective

• Based on the meter as a standard of measurement.
  • usage: "the metric system"; "metrical equivalents"
  • synonyms: metrical
• The rhythmic arrangement of syllables.
  • synonyms: measured, metrical