Visible tag, brand, mark, pictorial, or other informative matter, written, printed, stenciled, marked, embossed, or impressed on, or attached to, the packaging or container of a product.
Sources:
CNSSI 4009-2022
from
ISO/IEC 21371:2018
NIST SP 800-53 Rev. 5
The means used to associate a set of security attributes with objects in a human-readable form in order to enable organizational, process-based enforcement of information security policies.
Sources:
NIST SP 800-53 Rev. 5
under security marking