Hierarchical Faceted Descriptor Architecture

O*NET organizes descriptors using nested hierarchies where every level has explicit definitions and clear scope.

For example, under “Abilities” sits “Cognitive Abilities,” which contains “Verbal Abilities,” which contains specific abilities like “Oral Comprehension” and “Written Expression.” Each level is defined, not just labeled, with clear descriptions of what it includes.

The pattern recurs everywhere: Skills branch into Basic Skills and Cross-Functional Skills; Knowledge branches into Business/Management, Engineering/Technology, Mathematics/Science, and so on. Every intermediate node explains what it groups.

This isn’t just taxonomy, it’s documented taxonomy. The definitions do work. They constrain what can be added, guide placement decisions, and enable consistent interpretation across users.

Most organizational taxonomies skip this step. They create folders and labels but not definitions. The result: inconsistent classification, duplicate categories, and perpetual reorganization.

Related: 02-atom—crosswalk-definition, 06-molecule—ontology-design-patterns, 02-molecule—faceted-classification