The hosted domains feature of a hosting account refers to the amount of registered domain names which you could include in the exact same account. Registering a domain and hosting it are two different services even though many people consider them to be the same thing. While the registration means that you become the owner of a given domain name, the hosting part is what in fact allows you to have a site as this is where your data and email messages are going to be. Since these are two different services, you can register a new domain address with one company and host it with another one by changing its name servers (DNS) - the domain address shall work in the exact same way as if it was registered and hosted with the same company. Additionally, it is extremely important to know that changing the hosting means pointing the domain to an alternative company and not transferring it.