- Bounce Rate 
The percent of visitors that leave your site after only 1 page.
Also read How to Reduce Bounce Rate
- CPC 
Cost Per Click. CPC indicates measurement of cost on a per-click basis for contracts not based on click-throughs.
- CRO 
Conversion Rate Optimization.
- crt 
Click through rate. The amount of times an ad is clicked compared to the amount of times it is viewed.
- CTR 
Click-Through Rate is the number of times an advertisement is clicked upon over the number of times the advertisement is served.
- exit page 
Web page that readers leave your Web site from.
- Keyword prominence 
the placement of a keyword in the HTML source code of a web page. The higher up in the page a particular word is, the more prominent it is and thus the more weight that word is assigned by the search engine.
- lead 
A visitor performing an action (such as submitting a form) to get further information and begin the sales process.