Most countries in the world measure distance using the meter unit of distance. The U.S. and Liberia's unit of measure is the foot.

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  • On October 21, 1983, the length of the meter was adjusted. Originally defined in 1795 as one ten-millionth the distance from the Equator to the North Pole, the measurement went through a series of refinements as scientific knowledge advanced. Finally, in 1983, the International Committee for Weights and Measures redefined the meter as “the distance travelled by light in a complete vacuum in 1/299,792,458th of a second.”

    The meter is a standard unit of length in the International System of Units (SI), the system of measurement used throughout most of the world. A meter is equivalent to 3.3 feet in the United States customary units, the system used in the U.S.

  • Term Part of Speech Definition Encyclopedic Entry
    adjust Verb

    to change or modify something to fit with something else.

    Equator Noun

    imaginary line around the Earth, another planet, or star running east-west, 0 degrees latitude.

    Encyclopedic Entry: equator
    equivalent Adjective

    roughly equal or the same as something else.

    measurement Noun

    process of determining length, width, mass (weight), volume, distance or some other quality or size.

    North Pole Noun

    fixed point that, along with the South Pole, forms the axis on which the Earth spins.

    Encyclopedic Entry: North Pole
    vacuum Noun

    area of empty space.