Definitions for "Frequency Cap"
The maximum number of times or length of times a site visitor will be shown the same or related advertisements.
This is a limit on how many times an ad (usually a pop-up) will be shown to a visitor. For example you might set a frequency cap to limit a pop-up to only be shown once for every 10 pages a visitors to your site views.
restriction on the amount of times a specific visitor is shown a particular advertisement.