Short answer
Entity SEO is the practice of making a search engine resolve a business, person or product as one distinct thing rather than a set of unconnected mentions. It works through consistent naming, a consistent address and contact details, linked structured data, and corroborating references on independent sites.
Also called: Entity optimization, Knowledge graph optimization
The mechanism is disambiguation. Engines and language models build a graph of entities and relationships; a business whose name, address and description vary across its own pages and its directory listings produces several weakly-connected nodes instead of one well-supported one. Consistency is what merges them.
This is why entity work is largely off-site. A stable @id in your structured data connects your own pages to one another; independent references — directories, professional profiles, press, review platforms — are what allow an engine to confirm the entity exists outside its own marketing.
Related terms
Structured Data (Schema Markup)
Structured data is machine-readable markup, usually JSON-LD following the schema.org vocabulary, that states explicitly what a page is about: that this string is a price, that one an opening time, this entity the organisation publishing the page.
E-E-A-T (Experience, Expertise, Authoritativeness, Trust)
E-E-A-T is the framework in Google’s Search Quality Rater Guidelines used to judge content quality: demonstrated first-hand Experience, subject Expertise, recognised Authoritativeness, and Trust.
Local SEO
Local SEO is optimisation for searches with geographic intent — queries naming a city, or carrying implicit "near me" intent.
NAP Consistency
NAP consistency means a business publishes exactly the same name, address and phone number everywhere it appears online — its own site, its business profile, directories, and social pages.
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