Bounce rate is the percentage of single-page visits or web sessions. It is the percentage of visits in which a person leaves your website from the landing page without browsing any further.
“The percentage of single-page sessions”
Bounce rate is an online marketing metric that refers to the percentage of visitors who land on one page of your website and leave without viewing any other pages. As a metric that tracks single-page visitors, bounce rate reflects your effectiveness at retaining visitors.