CRO (Conversion Rate Optimization) with another word conversion optimization. Those conversions are goals you try to achieve with your website. Your goal is to convert online visitors into customers: that is the ultimate goal of your website.
What is a CRO analysis?
A CRO analysis is a way to use data and user feedback to improve your website. By 'conversion' we mean turning visitors into paying customers.
A CRO specialist is involved in conversion optimization. These are all the improvements to a website aimed at getting more visitors to convert on your website, thus turning them into customers.