When an AI grounds an answer about your brand, it links to sources. Cited Pages is the set of unique URLs it pulls from — your own product pages and docs, plus the third-party pages (retailers, reviews, roundups, forums) the engines lean on.
It answers two useful questions at once: which of your own pages are doing the work (so you can double down on them), and which third-party pages the engines trust in your category (so you know where earned coverage actually moves the needle). Often the most-cited pages aren't yours at all — which is exactly the signal that you need to get included in those independent sources.
One counting note: a URL cited by several engines is still one unique page, so per-engine counts can sum higher than the overall unique total. Read alongside Citation Coverage, which turns this into a percentage.