la.wikipedia.org/wiki/Situs_interretialis

The article's lead defines a website as a single web page ("pagina interretialis"). Authoritative web references distinguish those two terms.

• MDN separately defines a web page as "A document that can be displayed in a web browser" and a website as "A collection of web pages grouped together into a single resource," later phrased as "a collection of linked web pages (plus their associated resources) that share a unique domain name."
• Section508.gov says websites function through "a collection of interconnected web pages" and explicitly states that "A website ... consists of many web pages linked together under a common domain name."
• NIST's glossary defines a website as "A set of related web pages that are prepared and maintained as a collection in support of a single purpose."

So the problem is not merely wording style: the sentence collapses two different concepts. A web page is one document/page; a website is the broader site/collection that contains one or more pages and related resources. That makes the quoted definition inaccurate as a general definition of "website."