Hierarchy classification:

1. top of the aat hierarchies
2. Physical Attributes Facet
3. Attributes and Properties (hierarchy name)
4. [attributes and properties by specific type]
5. form attributes
6. shape (form attribute)
7. geometric shape

Anotations

Scope note:

Outline or form delimited by two ends that are equal and parallel circles, and the intervening curved surface is such as would be traced out by a straight line moving parallel to itself with its ends in the circumferences of these circles.