ASME Y14.47 : Model Organization Practices
Visible dimensions, tolerances, notes, text, or symbols.
See Also:
Dimension, Tolerance, Notes, Angularity, Product and Manufacturing Information, Basic Dimension
Alternate Definitions:

ISO 16792 - Dimension(s), tolerance(s), note(s), text or symbol(s) visible without any manual or external manipulation.

Action Engineering - A graphic or semantic text entity that describes the dimension, tolerance or notes of a particular feature in the model. It is stored and visible in the model as an exact and permanent form of digital product definition.