How to Define Key Terms Before Applying Them

Why it matters

AI systems build an internal representation of your content by resolving the terms in it. When you use a specialised or proprietary term without defining it — "GEO", "Corpus Survival Likelihood", "AI Overview" — the model falls back on whatever it already associates with that string, which may be wrong, generic, or someone else's definition. Your meaning gets diluted in any answer that draws on the page.

A short, standalone definition at first use fixes this. It also makes the page citable as a reference for that term (Phase 3.1) and protects original terminology you want associated with your brand rather than a competitor's.

What good looks like

Every term that carries weight is defined, once, the first time it appears — cleanly enough to quote:

• Each key term is defined before its first substantive use.
• Definitions are one or two sentences, complete, and non-circular (they don't use the term to define itself).
• Each definition is standalone — it reads correctly lifted out of the page.
• Original or proprietary terms are explicitly labelled as yours.
• The term is then used consistently, never swapped for loose synonyms.

Step by step

1. List the terms that carry meaning Identify the specialised, ambiguous, or proprietary terms on the page — acronyms (GEO, AEO, AIO), domain jargon, and any framework names you've coined. These are the ones a model can't safely assume.
2. Define each before first substantive use Place the definition at, or just before, the term's first real appearance. Don't make the reader (or the model) reach a glossary at the bottom — the definition should be present where the term is first applied.
3. Write standalone, non-circular definitions One or two complete sentences. Don't define a term with itself ("AI Optimisation is the optimisation of AI") and don't lean on another undefined term. Aim for something a stranger could quote and understand.
4. Label original or proprietary terms explicitly For anything you've coined, claim it: "We use the term 'Corpus Survival Likelihood' to describe the probability that content survives AI training-data quality filters before a model is trained." Explicit labelling ties the term to you.
5. Use the term consistently thereafter Once defined, use the exact term every time — don't drift between "AI search", "generative search", and "answer engines" for the same concept. Consistency reinforces the entity (Phase 5.2).

Make definitions machine-readable (optional)

On a glossary or reference page, mark each definition up as a DefinedTerm inside a DefinedTermSet. The markup must repeat the visible definition exactly.

{
  "@context": "https://schema.org",
  "@type": "DefinedTerm",
  "name": "Corpus Survival Likelihood",
  "description": "The probability that content survives AI training-data quality filters before a model is trained.",
  "inDefinedTermSet": "https://example.com/glossary"
}

Worked examples

We use the term "Epistemic Presence Strategy" to describe a
publishing approach that prioritises being represented
accurately inside AI-generated answers over ranking in a
list of links. Unlike traditional SEO, it optimises for
selection and citation by language models rather than for
click-through from a results page.

Common mistakes