Entry page is the first page of a visit.

For each Entry Page URL, Matomo (Piwik) reports the number of Entrances (Visits that started on this page), Bounces (Visits that started on this page but left the website straight away) and Bounce rate.

You can see all entry pages in the report at Behaviour > Entry pages.

See also our glossary of analytics terms.

Previous FAQ: How do I force Matomo to only track Page URLs that belong to my website?