Goniometer

For other uses, see Goniometer (disambiguation).
Goniometer made by Develey le Jeune in Lausanne, late 18th–early 19th century

A goniometer is an instrument that either measures an angle or allows an object to be rotated to a precise angular position. The term goniometry derives from two Greek words, γωνία (gōnía) 'angle' and μέτρον (métron) 'measure'.[1] The protractor is a commonly used type in the fields of mechanics, engineering, and geometry.

The first known description of a goniometer, based on the astrolabe, was by Gemma Frisius in 1538.

  1. ^ Spencer, Leonard James (1911). "Goniometer" . In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 12 (11th ed.). Cambridge University Press. p. 234.