Taxonomy
A taxonomy is a classification system in WordPress used to group content into named terms.
Common built-in taxonomies include categories and tags. Custom taxonomies extend that model for project-specific content structures.
What it does
A taxonomy lets you organize and filter content by shared labels or structures.
It is commonly used to:
- Group related content
- Filter archives
- Improve editorial organization
- Support structured navigation and discovery
- Add meaning to a post type
Core concepts
Terms
A taxonomy contains terms. For example, a category taxonomy contains category terms.
Hierarchical vs non-hierarchical
Some taxonomies behave like categories with parent-child structure. Others behave like tags with flatter labeling.
Relationship to post types
Taxonomies usually attach to one or more post types.
They classify content, while the post type defines the content model itself.
Common use cases
- Categories and tags for blog content
- Industry, topic, or region filters for custom content
- Structured archives and filtering
- Adding extra editorial term meta to a content model
- Attaching ACF field data to terms when needed
Practical notes
- A taxonomy is for grouping content, not replacing the content model itself.
- A post type and taxonomy usually work together.
- Taxonomy terms can also be extended with custom fields in systems such as ACF or Meta Box AIO, often through term meta.
Frequently Asked Questions
Is a taxonomy the same as a post type?
No. A post type defines what the content is. A taxonomy defines how it is grouped or classified.
Are categories and tags taxonomies?
Yes. They are the most common built-in taxonomy examples in WordPress.
Can taxonomy terms have custom fields?
Yes. In many setups, term screens can be extended with custom fields, especially through ACF.