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. [structural elements and components for structural elements]
8. structural elements
9. [spanning and projecting structural elements]
10. [arches and arch components]
11. arches
12. [arches by location or context]

Anotations

Scope note:

Arches which separate the bays of vaults, particularly in a groin- or barrel-vaulted space; in a ribbed vault context, use "transverse ribs"; for arches across a nave or hall that support walls rather than vaults, use "diaphragm arches."