Term: dynamic viscosity, \(\eta\)
https://doi.org/10.1351/goldbook.D01877

Definition:
For a laminar flow of a fluid the ratio of the shear stress to the velocity gradient perpendicular to the plane of shear.

Related Terms:
1) viscosity (http://doi.org/10.1351/goldbook.V06627).
2) shear stress (http://doi.org/10.1351/goldbook.S05638).
3) gradient (http://doi.org/10.1351/goldbook.G02669).

Source: Green Book, 2nd ed., p. 13 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Citation: 'dynamic viscosity, \(\eta\)' 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.D01877

License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms.

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