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Citable

Definition

DefinedTerm

Also known as: schema.org/DefinedTerm, DefinedTermSet

DefinedTerm is a Schema.org type for a word, name, acronym or phrase that has a formal definition. It carries a name, a description that holds the definition, an optional termCode, and an inDefinedTermSet link to the DefinedTermSet — the glossary or classification — it belongs to. It is the natural markup for a glossary entry and tells a machine that a passage is a definition.

DefinedTerm sits under Intangible in the Schema.org hierarchy. Schema.org describes it as a word, name, acronym or phrase with a formal definition, and lists category systems, glossaries, dictionaries and product classifications as typical uses. A DefinedTermSet groups terms; it is itself a CreativeWork, so a whole glossary can have an author and a URL. Several properties elsewhere in the vocabulary, including keywords, accept a DefinedTerm as a value, which lets an article point at a controlled term rather than a free-text tag.

Definitions are among the most quoted passage types, and a definition marked as DefinedTerm with a stable @id becomes an entity other pages can reference. Every entry in this glossary emits markup in this shape:

json
{
  "@context": "https://schema.org",
  "@type": "DefinedTerm",
  "@id": "https://example.com/glossary/llms-txt",
  "name": "llms.txt",
  "description": "llms.txt is a proposed convention for a Markdown file …",
  "inDefinedTermSet": { "@type": "DefinedTermSet", "name": "Citable glossary" }
}

Keep the description identical to the visible definition, and keep both self-contained: name the term in the first few words so the sentence still makes sense when quoted alone. The Schema.org entry places the type among its neighbours, and Structured data for AI answers shows how to generate it from CMS fields.

Frequently asked questions

Should a glossary page use DefinedTerm or FAQPage?

Use DefinedTerm for the definition itself and FAQPage only for genuine question-and-answer pairs on the same page. A definition is not an answer to a question, and marking it as one misdescribes it. The two types can coexist: this site emits DefinedTerm for every glossary entry and adds FAQPage when the entry has FAQ items.

Related terms

Guides that use this term

  • Structured data

    Structured data for AI answers: the schema.org types that matter

    Structured data for AI answers is JSON-LD that labels what a page contains: Article or TechArticle for provenance (author, datePublished, dateModified, citation), FAQPage for question–answer pairs, DefinedTerm for definitions, Person with sameAs for authors, BreadcrumbList and WebSite for context, and SpeakableSpecification for the direct answer. Google requires no markup for AI features; its value is removing ambiguity, so generate it from the CMS fields that render the visible text.

    9 min read

  • Technical

    Modelling content for answer engines in a headless CMS!

    A headless CMS content model for answer engines makes every Answer Engine Optimization signal a constrained field, not an editorial habit: a required short answer with a maximum length, key takeaways, FAQ items, sources with URL validation, the author as a relation, and published and updated dates. JSON-LD, Markdown and llms.txt are then generated from those fields, so no representation can disagree with the page.

    9 min read