Term: angle
https://doi.org/10.1351/goldbook.A00346

Definition:
The angle between two half-lines terminating at the same point is the ratio of the length of the included arc of the circle (with its centre at that point) to the radius of the circle. Symbols: α, β, γ ... This is a quantity of dimension one with the SI unit radian (rad), but very often degrees of arc are used.

Related Terms:
1) radian (http://doi.org/10.1351/goldbook.R05036).
2) degrees of arc (<em>of arc</em>) (http://doi.org/10.1351/goldbook.D01560).

Source: Green Book, 2nd ed., p. 11 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Citation: 'angle' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.A00346

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