In a design system what do you call when defining unites, and style of time & dates that will be used?

In a design system what do you call when needing to define what measurements of units will be used and how they will display? Along with defining how dates & time will be used and displayed. For example all dates will appear 03-01-2023 and not 3/1/2023 or Wednesday, March 1, 2023.

Thanks.