Decigrade

Gon
Unit of	Angle
Symbol	ᵍ or gon
Unit conversions
1 ᵍ in ...	... is equal to ...
turns	1/400 turn
radians	π/200 rad
degrees	9/10°
minutes of arc	54′

The gradian is a unit of measurement of an angle, equivalent to 1/400 of a turn,9/10 of a degree, or π/200 of a radian.

It is also known as gon (from Greek γωνία/gōnía for angle), grad, or grade. In continental Europe, the French term centigrade was in use for one hundredth of a grad. This was one reason for the adoption of the term Celsius to replace centigrade as the name of the temperature scale.

The unit originated in connection with the French Revolution in France as the grade, along with the metric system, hence it is occasionally referred to as a "metric degree". Due to confusion with the existing term grad(e) in some northern European countries (meaning a standard degree, 1/360 of a turn), the name gon was later adopted, first in those regions, later as the international standard. In German, the unit was formerly also called Neugrad (new degree), likewise Nygrad in Swedish, Danish and Norwegian (also Gradian), and Nýgráða in Icelandic.

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