What is topical authority?

A site earns topical authority by covering a subject thoroughly, not by having one excellent page on it. One great article can rank well on its own, but authority is judged across the whole set of pages a site has on a topic, how many angles it covers, how consistently, and how well those pages connect to each other.

This matters more for AI visibility than for classic ranking. A system deciding which source to lean on for an answer often weighs how much of a subject a domain covers, not just whether one particular page ranks well for one particular query. A site with twenty solid articles on a subject can end up preferred over a competitor's single outstanding article on the same subject, even where that single article outranks it in ordinary search results.

Topical authority is not the same as being a large, well known site. A big general site with one page on a niche subject usually loses out, in this specific sense, to a small site that covers exactly that subject in real depth.