Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Components (hierarchy name)
4. components (objects parts)
5. [components by specific context]
6. architectural elements
7. [surface elements and surface element components]
8. surface element components

Anotations

Scope note:

Use both for the horizontal or vertical members dividing glazing areas into lights and supporting the panes, and for the vertical members separating panels in panel doors; for the uprights that divide openings set in a series, use "mullions."