https://www.nfsa.gov.au/sites/default/files/2023-11/Chapter%201%20Block%201000%20x%20745.jpg
Granularity
The random, spatial variation in the transmitting or reflecting properties of the developed photographic image.
A scientific measurement of graininess.
Granularity measurements provided by manufacturers can be compared.
https://www.nfsa.gov.au/sites/default/files/uploads/2010/10/13/grainularity.jpg
References
British Standard Glossary of Terms used in the Motion Picture Industry